A combined (human and porcine) mass chemotherapy program was tested in a controlled design in 12 village hamlets in the Peruvian highlands. A single dose of 5 mg of praziquantel was given to eliminate intestinal taeniasis in humans, and two rounds of oxfendazole (30 mg/kg) were administered to all pigs. The total population in the study villages was 5,658 resident individuals, and the porcine population at the beginning of the study was 716 pigs. Human treatment coverage was 75%, ranging from 69% to 80%. There were only a few refusals of owners for porcine treatment of their animals. The effect of the intervention was measured by comparing incidence rates (seroconversion in pigs who were seronegative 4 months before) in treatment versus control villages, before and up to 18 months after treatment. There was a clear effect in decreasing prevalence (odds ratio, 0.51; P < 0.001) and incidence (odds ratio, 0.39; P = 0.013) in the treatment area after the intervention, which did not leave to extinction of the parasite but stabilized in slightly decreased rates persisting along the follow-up period. Mass chemotherapy was effective in decreasing infection pressure in this hyperendemic area. However, the magnitude of the effect was small and did not attain the goal of eliminating transmission.

Keywords: TAENIA-SOLIUM; FIELD TRIAL; CYSTICERCOSIS; NEUROCYSTICERCOSIS; MEXICO; OXFENDAZOLE; VACCINATION; PERU; PIGS; INTERVENTION

The third and final diagnostic antigen of the lentil lectin purified glycoproteins (LLGP) extracted from the larval stage of Taenia solium has been characterized, cloned, and expressed. T24 is an integral membrane protein that belongs to the tetraspanin superfamily. It migrates at a position corresponding to 24-kDa and as it homodimer at 42-kDa. Antibodies from cysticercosis patients recognize secondary structure epitopes that are dependent upon correctly formed disulfide bonds. A portion of T24, the large, extracellular loop domain, was expressed in an immunologically reactive form in insect cells. When tested in a Western blot assay with a large battery of serum samples, this protein, T24H, has a sensitivity of 94% (101/107), for detecting cases of cysticercosis with two or more viable cysts, and a specificity of 98% (284/290). The identification and expression of T24H sets the stage for the development of an ELISA suitable for testing single samples and for large-scale! serosurveys that is not dependent upon the isolation and purification of antigens from parasite materials.

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Taenia solium is a cestode parasite that causes cysticercosis in humans and pigs. This study examined the antibody responses in pigs immunized with the TSOL18 and TSOL45-1A recombinant vaccines against T. solium cysticercosis. Immunization with these proteins induced specific, complement-fixing antibodies against the recombinant antigens that are believed to be associated with vaccine-induced protection against T. solium infection. Sera from immunized pigs were used to define the linear B-cell epitopes of TSOL18 and TSOL45-1A. Prominent reactivity was revealed to one linear epitope on TSOL18 and two linear epitopes on TSOL45-1A. These, and oncosphere antigens from other taeniid cestodes, contain a protein sequence motif suggesting that they may show a tertiary structure similar to the fibronectin type III domain (FnIII). Comparison of the location of linear antigenic epitopes in TSOL18 and TSOL45-1A within the proposed FnIII structure to those within related cestode vaccine antigens reveals conservation in the positioning of the epitopes between oncosphere antigens from different taeniid species.

Keywords: epitopes, fibronectin, Taenia solium, TSOL18, TSOL45-1A

The existence of latent Taenia solium post-oncospheral stages in file tissues of infected pigs has been postulated. To assess Whether Such structures exist and call be detected, we examined muscle Samples from cysticercosis-infected and uninfected pigs. Pork samples were homogenized, centrifuged, and resuspended in saline solution. Round microscopic structures of approximately 10 mu m with variable refringence were found in the pellets of all Samples from both infected and uninfected pigs. These became homogeneously red after staining With Sudan TV and disappeared after ether extraction. The only difference between Samples front infected and uninfected pigs was the presence of inflammatory cells and tissue necrosis debris in the former group. Taenia solium oncospheres were stained and observed for comparative purposes, before and after inoculation into pork, Control oncosphere, were ellipsoidal, had nucleated basophile cells in their interior, and showed red aggregates oil their surfaces when stained with 3% Sudan IV. While rounded microscopical Structures similar to those previously reported were found, these differed morphologically from oncospheres, were of a lipid nature, and Occurred in both infected and uninfected animals. No evidence Supporting the presence of latent postoncospheral stages of Taenia solium was generated in this series of experiments.

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Gonadotropins and GnRH have been used to electively induce ovulation in llamas and alpacas, but critical evaluation of the natural interval to ovulation after mating has not been performed nor has a direct comparison of the effects of natural mating versus hormone treatments on this interval and subsequent luteal development. The objectives of this study were to compare the effects of hormonal treatments and natural mating on ovulation induction, interval to ovulation, and luteal development in llamas. The ovaries of llamas were examined by transrectal ultrasonography once daily. Llamas with a large follicle were assigned randomly to be: (1) mated with an intact male (mated; n = 10); (2) given 5 mg of LH im (LH; n = 11); or (3) 50 mu g of GnRH im (GnRH; n = 10). Ultrasound examinations were performed every 4 h from treatment (day 0) to ovulation and thereafter once daily for 15 consecutive days to monitor CL growth and regression (n = 5 per group). Plasma progesterone concentrations were measured at days 0, 3, 6, 9, and 12 after treatment to evaluate CL function. The size of the largest preovulatory follicle at the time of treatment did not differ among groups (11 +/- 0.6, 10.5 +/- 0.8, 11.8 +/- 0.9 mm, for mated, LH, and GnRH groups, respectively; P = 0.6). No differences were detected among groups (mated, LH, and GnRH) in ovulation rate (80%, 91%, 80%, respectively; P = 0.6), or interval from treatment to ovulation (30.0 +/- 0.5, 29.3 +/- 0.6, 29.3 +/- 0.7 h, respectively; P = 0.9). Similarly, no differences were detected among groups (mated, LH, and GnRH) in maximum CL diameter (14.2 +/- 0.3, 13.2 +/- 0.5, and 13.0 +/- 10.7 mm, respectively; P = 0.5), the day of maximum CL diameter (7.6 +/- 0.2, 7.6 +/- 0.2, and 7.4 +/- 0.4 mm, respectively; P = 0.6), or the day on which the CL began to regress (12.3 +/- 0.3 [non-pregnant, n = 3], 11.8 +/- 0.6, 12.2 +/- 0.4, respectively; P = 0.4). The diameter of the CL and plasma progesterone concentrations changed over days (P < 0.0001) but the profiles did not differ among groups. In summary, ovulation rate, interval to ovulation, and luteal development were similar among llamas that were mated naturally or treated with LH or GnRH. We conclude that both hormonal preparations are equally reliable for inducing ovulation and suitable for synchronization for artificial insemination or embryo transfer program.

Keywords: camelids, corpus luteum, ovary, ovulation, progesterone

Cardiopulmonary pathology among children resident at high altitude in Tintaya, Peru: A cross-sectional study. High Alt. Med. Biol. 7:168-179, 2006.-Symptomatic high-altitude pulmonary hypertension and structural cardiac abnormalities related to high altitude have been reported previously. However, their true prevalence has not been systematically determined. We assessed clinical indicators of cardiovascular health or disease and correlated them with anatomic and physiologic cardiovascular features in preschool and schoolchildren living at 4000 m. We also estimated the prevalence of cardiovascular problems in the population, with emphasis on symptomatic high altitude pulmonary hypertension and structural cardiopathies. Three hundred and twenty-six children residents of Tintaya, Peru, were cross-sectionally studied. Methods included structured interviews, anthropometry and physical examination, arterial oxygen saturation, hemoglobin determination, electrocardiography, and echocardiography. The prevalence of structural cardiac problems was 1.5%, with less than 1% possibly attributable to high altitude. All children with structural cardiac abnormalities were identified by a focused physical exam prior to echocardiography. None were identified by the health interview. No symptomatic high altitude pulmonary hypertension was identified in the absence of underlying structural anomalies. The prevalence of structural cardiac problems was consistent with data from sea level. Active monitoring of the health status of a pediatric population at high altitude is valuable in the timely detection of cardiac abnormalities. Although our study children enjoyed generally excellent health, comparative, longitudinal studies are warranted to determine the incidence of high altitude cardiopulmonary problems and to identify risk factors and early markers for later disorders associated to life at high altitude. Our findings are applicable to children with some degree of high altitude genetic background and high mobility patterns to lower altitudes and living in comparatively good nutritional and socioeconomic conditions.

Keywords: pulmonary hypertension, structural cardiac abnormalities, cardiopulmonary development, chronic hypoxia, adaptation, children, high altitude

Background Endemic pemphigus foliaceus or fogo selvagem is an autoimmune skin disease characterized by the presence of subcorneal superficial blisters and antibodies of the immunoglobulin G4 (IgG4) class specific for the desmosomal glycoprotein, desmoglein 1. In Peru, no studies have been published on the seroprevalence of antibodies against desmoglein 1 in healthy subjects from endemic foci.
Subjects and methods This was a cross-sectional study. The sample included 82 healthy subjects, 41 from the Pueblo Libre community, a focus of endemic pemphigus foliaceus, and 41 from a nonendemic urban area in Pucallpa City. Enzyme-linked immunosorbent assay (ELISA) was used to determine the presence of antibodies against desmoglein 1. Samples were processed and tested at the Department of Dermatology and Cutaneous Surgery, School of Medicine, University of Miami, Miami, Florida.
Results It was found that 31.7% of healthy individuals (13 subjects) from the endemic focus had anti-desmoglein 1 antibodies. A statistically significant association was found between the distance from the endemic focus and the presence of antibodies against desmoglein 1 in subjects living within the endemic focus [Mantel-Haenszel odds ratio (OR), 3.34; P = 0.03; 95% confidence interval (CI), 1.06-10.48]. Agriculture as an occupation showed a statistically significant association with the presence of antibodies against desmoglein 1 (Mantel-Haenszel OR, 7.84; P < 0.001; 95% CI, 2.47-24.87).
Conclusions Antibodies against desmoglein 1 are present in healthy subjects exposed to an endemic focus of pemphigus foliaceus (fogo selvagem). Agriculture is associated with a high risk of development of antibodies against desmoglein 1 in the endemic focus of the Pueblo Libre community.

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A dot enzyme-linked immunosorbent assay (dot-ELISA) was standardized using excretory-secretory antigens of Toxocara canis for the rapid immunodiagnosis of human toxocartasis. Thirty patients with clinical signs of toxocartasis, 20 cases with other parasitic diseases, and 40 healthy subjects were tested A total of 0.2 ng of antigen per dot, serum dilution of 1:160 and dilution conjugate of 1:1000 were found optimal The sensitivity and specificity of the assay were 100 and 95%, respectively. Comparable sensitivity of dot-ELISA and the standard ELISA was obtained, but only 3 cross-reactions occurred in the dot-ELISA, compared with 6 in the standard ELISA. Dot-ELISA is simple to perform, rapid, and low cost Large-scale screening studies should be done to evaluate its usefulness under field conditions.

Keywords: Toxocara canis, toxocariasis, dot enzyme-linked immunosorbent assay, ELISA

Background. Persons living at high altitude (exposed to hypoxia) have a greater number of coronary and peripheral branches in the heart than persons living at sea level. In this study we investigated the effect of intermittent hypobaric hypoxia on myocardial perfusion in patients with coronary heart disease.
Methods and Results. We studied 6 male patients (aged >= 53 years) with severe stable coronary heart disease. All patients were born at sea level and lived in that environment. They underwent 14 sessions of exposure to intermittent hypobaric hypoxia (equivalent to a simulated altitude of 4200 m). Myocardial perfusion was assessed at baseline and after treatment with hypoxia by use of exercise perfusion imaging with technetium 99m sestamibi. After the sessions of hypoxia, myocardial perfusion was significantly improved. The summed stress score for hypoperfusion, in arbitrary units, decreased from 9.5+ to 4.5+ after treatment (P = .036). There was no evidence of impairment of myocardial perfusion in any patient after treatment.
Conclusions. Intermittent hypobaric hypoxia improved myocardial perfusion in patients with severe coronary heart disease. Though preliminary, our results suggest that exposure to intermittent hypobaric hypoxia could be an alternative for the management of patients with chronic coronary heart disease.

Keywords: myocardial perfusion, angiogenesis, hypoxia, altitude, coronary patient

We describe a new species of Cochranella from the Cordillera de Carpish, Departamento Huanuco, Peru. The new species is placed in the Cochranella, ocellata g roup and can be distinguished from all other species of Cochranella by having: (1) small white and dark purple spots on the dorsum; (2) a snout slightly protrud ing to truncate in lateral aspect; (3) and basal webbing between Fingers III and IV.

Keywords: centrolenidae, Cochranella ocellata group, Cordillera de Carpish, new species, Peru

An ethanol extract of the Peruvian plant Clavija procera, a member of the rare Theophrastaceae family, was fractionated using a colorimetric bioassay-guided protocol against Mycobacterium tuberculosis (MTB), yielding the oleanane triterpenoid aegicerin (1) as the active constituent. Its MIC values ranged between 1.6 and 3.12 mu g/mL against 37 different sensitive and resistant MTB strains (1 H37Rv, 21 susceptible clinical isolates, 2 INH-resistant clinical isolates, and 13 MDR clinical isolates).

Keywords: MYCOBACTERIUM-TUBERCULOSIS GROWTH; NATIONAL-CANCER-INSTITUTE; ALAMAR-BLUE ASSAY; COLORIMETRIC METHOD; PENTACYCLIC TRITERPENOIDS; ANTITUBERCULAR ACTIVITY; OLEANANE TRITERPENES; NATURAL-PRODUCTS; DRUG DISCOVERY; CONSTITUENTS

In July 2001, a Louisiana State University Museum of Natural Science expedition rediscovered the White-masked Antbird (Pithys castaneus) at a site along the Rio Morona in northwestern Departmento Loreto, Peru. Prior to this rediscovery, the species was known only from the type specimen, taken in 1937, and nothing was recorded concerning its natural history. The lack of additional specimens led to speculation that P. castaneus was a hybrid. Here, we present data demonstrating that the White-masked Antbird is a valid species, and we report the first observations of its behavior, habitat, morphology, and voice.

Keywords: Pithys castaneus, antbird, bird

We report the discovery of the first Deseadan South American land mammal "age" (SALMA: late Oligocene-?earliest Miocene) local fauna of Peru. The Deseadan SALMA fossils were found in the Upper Moquegua Formation at the summits of Cerro Pail de Azucar and nearby Cerro Mono. During our initial (August 2002) and subsequent (August 2003) visits. we recovered numerous remains of mesotheriid and notohippid notoungulates, as well as fragmentary remains of a small, indeterminate typothere notoungulate, macrauchcniid and proterotheriid litopterns, an indeterminate reptile, and a large, predaceous bird.

Keywords: Salla beds; Bolivia

Cyphocharax derhami, new species, is described from two localities in the northeastern portion of Peru. This species can be distinguished from its congeners by a combination of morphometric, meristic, and pigmentary features, most obviously the distinct bar of dark pigmentation extending posteroventrally from the rear of the orbit to the posterior margin of the opercle.

Keywords: Cyphocharax derhami, fish.

Base-line data were collected to examine the possible effects of the aquarium trade on Amazon fish populations in differentially-fished locations in the Departmento of Loreto, Peru. Fish abundance, species diversity (richness) and biomass were quantified at three locations with differential fishing pressure, including the Rio Nanay (high pressure), Rio Apayacu and Rio Arambassa (medium) and Rio Yanayacu-Pacaya-Samiria National Reserve (low). Seining results indicated that the location with the highest fishing pressure had reduced fish abundance, species diversity and biomass compared to the other locations. A similar trend was seen using minnow traps. There was no significant difference in abundance, diversity and biomass between the medium and low fishing pressure locations. Habitat differences (pH and conductivity) among the three locations accounted for < 13% of the observed variation, and thus it seemed possible that some of the decline in the Rio Nanay location could be tentatively attributed to increased fishing pressure. Although effects of pollution and habitat alteration could not be ruled out, this is one of the first studies to provide quantitative data on the effect of the freshwater aquarium trade on wild fish populations. While results suggest success in the protection of fishes for the aquarium trade in Pacaya-Samiria National Reserve, it also may be sustainable to establish limited levels of fishing, as was found in the medium fishing pressure locations, in order to promote economic opportunities and incentives for habitat preservation for indigenous communities.

Keywords: Amazon River Basin, aquarium trade, artisanal, fisheries, ornamental, overfishing

Lachesis venom plasminogen activator (LV-PA) is a 33-kDa serine proteinase isolated from bushmaster (Lachesis muta muta) snake venom, which activates the fibrinolytic system in vitro. This study has examined the effect of the plasma proteinase inhibitor alpha 2-macroglobulin (alpha 2-M) towards LV-PA and compares it with the effect on tissue type plasminogen activator (t-PA). The proteolytic activity of LV-PA alone or previously incubated with human plasminogen (Plg) on the large molecular mass protein substrates, dimethylcasein (DMC) and fibrinogen (Fg) was completely inhibited by human alpha 2-M. However, the synthetic peptides Tos-Gly-Pro-Lys-pNA and H-D-Pro-Phe-Arg-pNA (S-2302) were hydrolyzed with almost no reduction in rate. At pH 7.4 and 37 degrees C the proteinase (0.15 mu M over 15 min) interacted with alpha 2-M, and each mole of' alpha 2-M bound 2 mol of enzyme. Sodium dodecyl sulfate gel electrophoresis of reduced samples showed that the interaction of alpha 2-M with either LV-PA or t-PA preincubated with Plg resulted in the formation of similar to 90 kDa fragments and high molecular mass complexes (Mr 180 kDa), generated by the incubation mixture (LV-PA or t-PA) and Plg. The data suggest that LV-PA is a direct-type PA and its fibrinolytic effect can be reduced by alpha 2-M in vivo. Keywords: serineproteinase, alpha 2-macroglobulin, Lachesis muta, plasminogen activator, fibrinolysis

Aim: We examined whether the aqueous extract of Erythrina falcata, reputed to be a contraceptive in Peruvian folklore, could prevent pregnancy in the mouse.
Methods: Female mice on Day 1 of pregnancy were given aqueous extract of E. falcata or tap water (control) orally for 4 days. On Day 4 of pregnancy, animals were killed and the embryos were flushed from oviducts and uterus to examine their developmental stage, cell number, mitotic index and micronuclei frequency. Other mice were killed on Day 12 of pregnancy to determine the number of implantation sites.
Results: Ingestion of E. falcata diminished the percentage of embryos that progressed to blastocyst stage, reduced the cell number and mitotic index, and increased the micronuclei frequency of early embryos. The number of implantation sites was also reduced in females treated with E. falcata.
Conclusion: The aqueous extract of E. falcata, ingested during early pregnancy, disturbs preimplantation embryo development and implantation in the mouse. These results provide the first experimental evidence of the contraceptive properties of the aqueous extract of E. falcata.

Keywords: native plants, Erythrina falcata, contraceptive, preimplantation development, implantation, mouse

Recent results on magnetoresistance in a two dimensional electron gas (2DEG) under crossed magnetic and microwave fields show a new class of oscillations, suggesting a new kind of zero-resistance states. We consider the problem from the point of view of the electronic structure dressed by photons due to a in plane linearly polarized ac field. In the strong modulation limit predictions on dressed Hofstadter spectra are discussed, which could be of interest since the bare spectra have been observed in the past few years.
Keywords: 2DEG, Hofstadter butterfly, dressed states, magnetic field, dynamic localization

We use high-quality VLT/UVES published data of the permitted O i triplet and Fe II lines to determine oxygen and iron abundances in unevolved ( dwarfs, turnoff, subgiants) metal-poor halo stars. The calculations have been performed both in LTE and non-LTE (NLTE), employing effective temperatures obtained with the new infrared flux method (IRFM) temperature scale by Ramirez & Melendez, and surface gravities from Hipparcos parallaxes and theoretical isochrones. A new list of accurate transition probabilities for Fe II lines, tied to the absolute scale defined by laboratory measurements, has been used. Interstellar absorption has been carefully taken into account by employing reddening maps, stellar energy distributions and Stromgren photometry. We find a plateau in the oxygen-to-iron ratio over more than 2 orders of magnitude in iron abundance (-3.2 < [Fe/H] < -0.7), with a mean [O/Fe] = 0.5 dex (sigma = 0.1 dex), independent of metallicity, temperature, and surface gravity. The flat [O/Fe] ratio is mainly due to the use of adequate NLTE corrections and the new IRFM temperature scale, which, for metal-poor F/early G dwarfs is hotter than most T-eff scales used in previous studies of the O I triplet. According to the new IRFM T-eff scale, the temperatures of turnoff halo stars strongly depend on metallicity, a result that is in excellent qualitative and quantitative agreement with stellar evolution calculations, which predict that the T-eff of the turnoff at [Fe/H] = -3 is about 600 - 700 K higher than that at [Fe/H] = -1. Recent determinations of H alpha temperatures in turnoff stars are in excellent relative agreement with the new IRFM Teff scale in the metallicity range -2.7 < [Fe/H] < -1, with a zero-point difference of only 61 K.
Keywords: atomic data, cosmic rays, Galaxy : halo, stars : abundances, stars : atmospheres, stars : fundamental parameters, stars : Population II, Sun : abundances

In this work, we present X-ray diffraction, Raman spectroscopy and magnetizations measurement of the system CaLaBaCu3-X(PO4)(X)O7-delta with X = 0.1, 0.3, 0.5 which is superconductor with the critical temperatures: T-c = 20 K to X = 0.1, T-c = 14 K to X = 0.3 and T-c = 20 K to X = 0.5. Samples were prepared by the solid-state reaction method under normal conditions of pressure and temperature, replacing 0.1, 0.3 and 0.5 of phosphate (PO4)(3-) in the Cu(1) site of CaLaBaCu3O7-delta (La1113). The X-ray diffraction patterns revel the presence of BaCuO2 and CuO as secondary phases, BaCuO2 increases as phosphate increases in the samples. Rietveld refinements suggest orthorhombic crystalline structures, belonging to Pmmm spatial group, for all the samples; nevertheless there are variations in the cell parameters. T-c's were determinate by measurements of magnetization using a SQUID detection system, which indicate variation of T-c according with phosphate concentrations. An study by Raman spectroscopy is added. Finally, the chemical analysis by EDX of a scanning electronic microscope (Phillips XL30) indicates the appropriates amounts of phosphorus in the samples.
Keywords: superconductors, chemical synthesis, X-ray diffraction

We present X-ray diffraction and magnetization measurements of the compound [Y0.8Ca0.2]SrBaCu3-x(BO3)(x)O7-delta with 0.1 <= x <= 0.5. Samples were prepared by the solid state reaction method under normal conditions of pressure and temperature, and replacing amounts of borate (BO3)(3-) in the Cu(1) site of [Y0.8Ca0.2]SrBaCu3O7-delta. The X-ray diffraction patterns reveal a monophasic compound. Rietveld refinements were done with the consideration of an orthorhombic crystalline model, belonging to Pmmm spatial group for most the samples; nevertheless there are significant variations in the cell's parameters. We propose the crystalline structure for the [Y0.8Ca0.2]SrBaCu3-x(BO3)(x)O7-delta with the indication of the borate occupying the Cu(1) site. The T-C were determinate by the measurements of magnetization versus temperature using a SQUID detection system, which indicates the T-C vary according with the concentration of borate. For instance to x=0.10; 0.30 and 0.50, the T-C's are 35, 38 and 28 K, respectively.
Keywords: superconductors, chemical synthesis, X-ray diffraction

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