Redescripción de Haliotrematoides mediohamides (Monogenea: Dactylogyridae), un parásito branquial del sargo Calamus brachysomus (Perciformes: Sparidae) del océano Pacífico oriental

The monogenean Haliotrematoides mediohamides Kritsky & Mendoza-Franco, 2009 (Monogenea: Dactylogyridae) is redescribed based on examination of the type specimen (paratypes) and newly collected specimens parasitizing the gills of the Pacific porgy, Calamus brachysomus (Lockington, 1880) (Perciformes: Sparidae) (type host), a neritic fish captured off the coastal zone of Puerto Pizarro, Tumbes, Peru. Even though this monogenean was described 12 years ago, that description did not report some of the unique morphological features of H. mediohamides and neither did it offer a whole-mount drawing of this species. The most important characteristics of H. mediohamides are: 1) a male copulatory organ with hook-shaped distal end, 2) a non-coiled vaginal duct, 3) numerous secretory gland-cells associated with the peduncle, 4) a chandelier-shaped extrinsic adductor muscles articulated with superficial roots of the anchors, 5) a single tadpole-shaped prostatic reservoir, and 6) a vas deferens anteriorly convoluted. In addition, the first whole-mount drawing of H. mediohamides, as well as morphometric data are provided. Haliotrematoides mediohamides represents the first record of Haliotrematoides in South America. Haliotrematoides mediohamides is the third dactylogyrid species recorded to infect C. brachysomus in Peru.

Six new species of Rhamnocercus Monaco, Wood & Mizelle, 1954 (Monogenea: Diplectanidae) infecting the gills from South American sciaenid fishes

A parasitological survey searching diplectanids (Monogenea: Diplecatnidae) infesting the gills of marine fishes from South America was carried out during the 2019-2020 period. The gills of four sciaenid species, 2 Cheilotrema fasciatum Tschudi, 1 smalleye croaker Nebris microps Cuvier, 2 royal highhat Pareques lanfeari (Barton), and 1 minor stardrum Stellifer minor (Tschudi), were sampled. Six new species of Rhamnocercus Monaco, Wood & Mizelle, 1954 were described: Rhamnocercus chacllae n. sp. and Rhamnocercus chaskae n. sp. from P. lanfeari, Rhamnocercus fasciatus n. sp. from C. fasciatum, Rhamnocercus microps n. sp. from N. microps, and Rhamnocercus rimaci n. sp. and Rhamnocercus tantaleani n. sp. from S. minor. Rhamnocercus chacllae n. sp. can be differentiated from its congeners by its L-shaped male copulatory organ (MCO) and by having an anteromedial slight notch at ventral bar. Rhamnocercus chaskae n. sp. differs from the other species of the genus by its long and straight MCO with bifid distal end and by having haptoral accessory spines at level of ventral bar with quadrifid distal portion. Rhamnocercus fasciatus n. sp. is characterized by possessing a straight and long MCO with truncated distal end, haptoral accessory spines at level of ventral bar with bifid distal portion, dorsal bars with a knob at lateral extremity, and a large vagina with bell-shaped. Rhamnocercus microps n. sp. differs from all congeners mainly by having a short and straight MCO with the distal end of internal tube spatulate and uncovered by external tube. Rhamnocercus rimaci n. sp. is can be distinguished from all other species of Rhamnocercus by having an almost J-shaped MCO with the distal end of external tube slight expanded and the distal end of internal tube narrow and uncovered by external tube. Rhamnocercus tantaleani n. sp. is mainly characterized by its MCO, which is tubular and straight, having the distal end of external tube bifurcated (right branch well-expanded and left branch narrow) and the distal end of internal tube enveloped by left branch of the external tube. This is the first data on the parasites of P. lanfeari, a little known, but popular fish in local markets from Peru. Rhamnocercus microps n. sp. is the first described species of Rhamnocercus in Brazil. The present finding brings to 12, the number of known species of Rhamnocercus. A key to Rhamnocercus species is provided.

First Data on the Parasites of the Pacific Kingcroaker Menticirrhus elongatus (Perciformes: Sciaenidae): Description of a New Species of Rhamnocercoides (Dactylogyridea: Diplectanidae)

INTRODUCTION

A new monogenean, Rhamnocercoides lambayequensis n. sp. (Dactylogyridea: Diplectanidae), is described based on the specimens collected from the gills of the Pacific kingcroaker Menticirrhus elongatus (Günther 1864) (Perciformes: Sciaenidae), a demersal fish endemic to Eastern Pacific, captured off the South American Pacific coast, Lambayeque Region, Peru.

MATERIALS AND METHODS

Monogeneans were fixed in hot 4% formalin. Some monogeneans were transferred directly onto a slide in a drop of glycerin-ammonium picrate mixture (GAP). Others were mounted stained with Gomori's trichrome in Canada balsam. Drawings were made using of a drawing tube.

RESULTS

The new species is mainly characterized by its MCO, which is tubular and straight, with external (distally expanded and bifurcated) and internal tubes (distally uncovered by external tube). Rhamnocercoides lambayequensis n. sp. is also characterized by having the following features: a weakly sclerotized almost pyriform vagina; haptoral acicular spines with expanded distal portion and by having a small group of haptoral accessory spines associated with haptoral lobes arranged as spikes.

CONCLUSIONS

This is the first data on the parasites of M. elongatus, a little known, but popular fish in local markets. The present finding brings to two, the number of known species of Rhamnocercoides Luque and Iannacone 1991, and represents the sixth described marine diplectanid species infecting sciaenid fishes from Peru.

Glossidiella peruensis sp. nov., a new digenean (Plagiorchiida: Plagiorchiidae) from the lung of the brown ground snake Atractus major (Serpentes: Dipsadidae) from Peru

During a survey of helminth parasites of the brown ground snake, Atractus major Boulenger, 1894 (Serpentes: Dipsadidae) from Moyobamba, region of San Martin (northeastern Peru), a new species of Glossidiella Travassos, 1927 (Plagiorchiida: Plagiorchiidae) was found and is described herein based on morphological and ultrastructural data. The digeneans found in the lung were measured and drawings were made with a drawing tube. The ultrastructure was studied using scanning electron microscope. Glossidiella peruensissp. nov. is easily distinguished from the type- and only species of the genus, Glossidiella ornata Travassos, 1927, by having an oblong cirrus sac (claviform in G. ornata), distinctly ovate testes (rounded testes in G. ornata) and button-like papillae on the dorsal edge of the oral sucker region (absent in G. ornata). In addition, G. peruensissp. nov. differs from G. ornata by possessing a longer distance between testes and substantially wider oral and ventral suckers. This is the first time that a species of digenean is described and reported parasitizing snakes in Peru.

Hypanocotyle bullardi n. gen. n. sp. (Monogenea: Hexabothriidae) from gill of the diamond stingray Hypanus dipterurus (Jordan et Gilbert) (Myliobatiformes: Dasyatidae) in the Southeastern Pacific Ocean off Peru

A new genus and species of monogenean belonging to Hexabothriidae, Hypanocotyle bullardi n. gen. n. sp., is described based on specimens collected from the gill filaments of the diamond stingray, Hypanus dipterurus (Jordan et Gilbert) (Myliobatiformes: Dasyatidae), a demersal chondrichthyan collected off the coast of Callao, Peru. Hypanocotyle n. gen. has the following combination of diagnostic features that differentiate it from other hexabothriid genera: haptor symmetrical; vasa efferentia having proximal (narrow, with thin glandular wall) and distal (expanded, interlaced, with thick glandular wall) portions, joining medially to form vas deferens; vas deferens having proximal (expanded, sinuous, with thick glandular wall) and distal (narrow, strongly sinuous, with thin glandular wall) portions; male copulatory organ unarmed, proximal portion slightly sinuous and tube-like, distal portion funnel-shaped; prostatic glands present, distributed around of the MCO; seminal receptacle present; ootype lacking longitudinal rows of large cells (no oötype côtelé); vaginae parallel, with well-differentiated proximal (glandular, narrow, tube-like, slightly sinuous) and distal (musculoglandular, convoluted) portions; gland cells surrounding the vaginal duct along the entire length of distal portion, densely clustered in middle portion; uterine eggs with 2 elongate filaments. Phylogenetic reconstructions by maximum-likelihood method, based on newly obtained partial 18S and 28S sequences, shows that H. bullardi n. gen. is included within the family Hexabothriidae, order Diclybothriidea. This is the second hexabothriid genus recorded from a diamond stingray (Dasyatidae), and the fourth hexabothriid species recorded from Peru. A key to hexabothriid genera is provided.

Diplectanids (Monogenea) parasitic on sciaenid fish from Peru with the proposal of Pseudorhamnocercoides n. gen., the description of Rhamnocercus dominguesi n. sp. and the redescription of Rhamnocercoides menticirrhi Luque and Iannacone, 1991

Rhamnocercoides menticirrhi Luque and Iannacone, 1991 is redescribed from newly collected material of snakehead kingcroaker Menticirrhus ophicephalus (Jenyns, 1840) from Peru, and as a result of this redescription, the diagnosis of Rhamnocercoides is emended. Rhamnocercus dominguesi n. sp. is described from the Peruvian banded croaker Paralonchurus peruanus (Steindachner, 1875). It differs from congeneric species mainly in the morphology of the male copulatory organ (with distal and proximal portion of the external tube expanded and distal portion of the internal tube uncovered by external tube) and the number of peduncular spines (18-22, arranged in 2 longitudinal rows). Pseudorhamnocercoides n. gen. is proposed for species with two longitudinal rows of peduncular spines with anterior and posterior roots, two longitudinal rows of acicular spines associated with peduncular spines, a medial constriction in the ventral bar and more than six haptoral accessory spines at level of the ventral bar with fan-like distal extremity. Rhamnocercoides stichospinus (Seamster and Monaco, 1956) is transferred to Pseudorhamnocercoides n. gen as Pseudorhamnocercoides stichospinus (Seamster and Monaco, 1956) n. comb (assigned as type species).

Monocotyle luquei n. sp. (Monogenea: Monocotylidae), from the gills of diamond stingray Dasyatis dipterura (Jordan and Gilbert, 1880) (Myliobatiformes: Dasyatidae), in the South Pacific

Monocotyle luquei n. sp. (Monogenea: Monocotylidae) was described from gills of diamond stingray Dasyatis dipterura (Jordan and Gilbert, 1880) (Dasyatidae) off Peru. The new species can be differentiated from the other species of the genus by the combination of the following characteristics: (1) accessory sclerites on the dorsal posterior surface of the body absent, (2) only one testis is present, (3) 1-2 loops in the copulatory organ, (4) the male copulatory organ with a sclerotized accessory piece, (5) shape of five sclerites in marginal papillae, (6) size of anchor and (7) posterolateral septa bifurcated. This is the first record of species of Monocotyle Taschenberg, 1878 from the southern Pacific.

Comunidad de Helmintos Parásitos del Sapo Espinoso Rhinella spinulosa (Wiegmann, 1834) (Anura: Bufonidae) de Perú

El objetivo de la presente investigación fue evaluar la comunidad de los metazoos parásitos del sapo espinoso Rhinella spinulosa de Perú y elucidar si el sexo y la longitud total de los anfibios hospederos están estructurando sus comunidades de parásitos. Se trabajó con 90 especímenes de R. spinulosa adquiridos entre mayo de 2009 y octubre de 2010. La cavidad corporal, tubo digestivo, vejiga urinaria, pulmones y musculatura fueron examinados para la búsqueda de metazoos parásitos. Siete taxas de metazoos parásitos fueron colectados: un digeneo [Gorgoderina chilensis (Gorgoderidae), en vejiga urinaria], un cestodo [Cylindrotaenia aff. americana (Proteocephalidae) en intestino delgado], cuatro nematodos [Aplectana hylambatis y A. vellardi (Cosmocercidae) en intestino grueso, Hedruris moniezi (Hedruridae) en estómago y Rhabdias aff. pseudosphaerocephala (Rhabdiasidae) en pulmones] y un acantocefalo [Pseudoacanthocephalus lutzi (Echinorhynchidae) en intestino delgado]. Se observó una correlación positiva entre la talla y la abundancia media de R. aff. Pseudosphaerocephala, así como asociación entre el sexo y la abundancia media de G. chilensis, A. hylambatis y R. aff. pseudosphaerocephala. G. chilensis mostró dependencia con el sexo de R. spinulosa. Los tres índices de agregación (Índice de Dispersión, Índice de Discrepancia de Poulin y K de la ecuación binomial negativa) indicaron una distribución contagiosa. La mayoría de los valores de diversidad alfa de las infracomunidades parasitarias fueron menores que los del componente comunitario.

Comunidad Parasitaria de Cabinza Isacia conceptionis (Cuvier & Valenciennes, 1830) (Perciformes: Haemulidae) en la Zona de Chorrillos, Lima, Perú

El objetivo del presente trabajo fue evaluar la comunidad parasitaria de la cabinza Isacia conceptionis (Cuvier y Valenciennes, 1830) (Haemulidae) (n=123), procedente del Terminal Pesquero de Chorrillos, Lima, Perú, entre diciembre de 2010 a marzo de 2011. Los parásitos se fijaron, preservaron y cuantificaron mediante procedimientos estandarizados. Se colectaron 95 parásitos de siete especies, con una abundancia media total de 0.77. El promedio de la riqueza de especies fue 0.46. Los cuatro parásitos con mayor prevalencia y abundancia media fueron: Choricotyle isaciencis Oliva, González, Rus & Luque, 2009, Corynosoma obtuscens (Lincicome, 1943), Proleptus carvajali Fernández y Villalba, 1985, y Clavella simplex Castro y Baeza, 1985. Los parásitos de I. conceptionis señalan que los tres índices de agregación [Dispersión (ID), Discrepancia de Poulin (D) y Binomial Negativa (k)] mostraron mayormente una distribución agregada. La prevalencia de C. isaciencis estuvo correlacionada con la longitud total del pez hospedero. En relación al kn (factor de condición relativo), no se observó que los peces parasitados con C. obtuscens, C. isaciencis, ectoparásitos y endoparásitos presentasen valores más altos en comparación con los peces no parasitados. El índice gonadosomático (IGS) no se relacionó con ninguno de los índices de ecología parasitaria. Los índices de equidad de la parasitofauna mostraron valores relativamente altos y, en cambio, los índices de dominancia fueron bajos. Los índices de interactividad (CC50) de ectoparásitos y endoparásitos indican que las comunidades son aisladas.

Optimización de técnicas para aislamiento y ruptura de quistes de Giardia spp

Objetivos: Optimizar y evaluar técnicas de ruptura de quistes de Giardia spp para obtener ADN, paso previo a pruebas moleculares. Diseño: Experimental. Institución: Instituto de Medicina Tropical Daniel A. Carrión, Facultad de Medicina, UNMSM. Material biológico: Muestras de heces con quistes de Giardia. Intervenciones: Las muestras de heces con abundantes quistes de Giardia fueron evaluadas con una técnica de obtención de quistes y tres de desenquistamiento. Técnica 1: sedimentación rápida; el sedimento fue lavado varias veces con agua destilada y centrifugado. Para el desenquistamiento, los quistes fueron incubados a: Técnica A: 37°C con bilis de cerdo. Técnica B: con HCl 0,1 N y luego hipoclorito de sodio al 20% a 37°C. Técnica C: Por duplicado, cinco ciclos de congelamiento (-20°C), calentamiento (80°C) y luego papaína a 60°C. Se contó en cámara Newbauer el número de quistes antes y después de cada prueba. Principales medidas de resultados: Mayor número de trofozoítos. Resultados: La técnica B rindió mayor número de trofozoítos que la A. La C no tuvo éxito. Conclusiones: Desenquistar con HCl 1N e hipoclorito de sodio al 20% a 37°C fue buen método para obtener trofozoítos de Giardia.

Crataegus laevigata decreases neutrophil elastase and has hypolipidemic effect: a randomized, double-blind, placebo-controlled trial

Crataegus laevigata is a medicinal plant most commonly used for the treatment of heart failure and psychosomatic disorders. Based on previous experimental findings, this double-blind placebo-controlled study was aimed at finding beneficial effects of C. laevigata on biomarkers of coronary heart disease (CHD). The study included 49 diabetic subjects with chronic CHD who were randomly assigned to the treatment for 6 months with either a micronized flower and leaf preparation of C. laevigata (400 mg three times a day) or a matching placebo. Blood cell count, lipid profile, C-reactive protein, neutrophil elastase (NE) and malondialdehyde were analyzed in plasma at baseline, at one month and six months. The main results were that NE decreased in the C. laevigata group compared to the placebo group. In the C. laevigata group, baseline figures (median and interquartile range) were 35.8 (4.5) and in the placebo group 31 (5.9). At the end of the study, values were 33.2 (4.7) ng/ml and 36.7 (2.2) ng/ml, respectively; p<0.0001. C. laevigata, added to statins, decreased LDL cholesterol (LDL-C) (mean±SD) from 105±28.5 mg/dl at baseline to 92.7±25.1 mg/dl at 6 months (p=0.03), and non-HDL cholesterol from 131±37.5 mg/dl to 119.6±33 mg/dl (p<0.001). Differences between groups did not reach statistical significance at 6 months. No significant changes were observed in the rest of parameters. In conclusion, C. laevigata decreased NE and showed a trend to lower LDL-C compared to placebo as add-on-treatment for diabetic subjects with chronic CHD.

Microalbuminuria and oxidative stress in essential hypertension

OBJECTIVE

To assess the relationship between microalbuminuria and oxidative stress in mononuclear peripherals cells in essential hypertension.

METHODS

A total of 123 hypertensive patients in absence of antihypertensive treatment were included. A 24-h ambulatory blood pressure (BP) monitoring was performed using a Spacelabs 90207 monitor, and microalbuminuria was measured in 24-h urine collections. Oxidized/reduced glutathione ratio and the content of malondialdehide and damaged base 8-oxo-2'-deoxyguanosine in genomic and mitochondrial DNA were measured in peripheral mononuclear cells.

RESULTS

In the 29 (24%) microalbuminuric subjects, the amount of reduced glutathione was significantly lower and the ratio oxidized/reduced glutathione was significantly higher than in the normoalbuminuric subjects. In contrast, the simultaneous measurement of the levels of malondialdehide and 8-oxo-2'-deoxyguanosine from both genomic and mitochondrial DNA oxidation did not achieve statistical significance between the two groups. Subjects with the highest oxidized/reduced glutathione ratio tertile showed the highest urinary albumin excretion (UAE) (P = 0.04 for trend). In a stepwise multiple regression analysis, oxidized/reduced glutathione ratio was the main significant determinant of UAE accounting for the 9% of the variance when 24-h mean BP, age, sex, body mass index, glucose and total cholesterol were included in the model.

CONCLUSIONS

Oxidative stress seems to be a determinant of UAE independent of BP levels even in hypertensive subjects.

[Risk factors for low birth weight and intrauterine growth retardation in Santiago, Chile]

An epidemiologic case-control study to ascertain the determinants of low birthweight was carried out in Santiago, Chile, from January to December 1989. The cases were defined as livebirths < 2500 g. The controls were livebirths > or = 2500 g of birthweight. All cases and a random sample (1:1) of controls were selected among 8,254 singleton births occurring at the El Salvador Hospital in the Eastern area of Santiago. These deliveries represented 50% of institutional deliveries in the area. Home deliveries (2%) and private hospital deliveries were not included in the study. Information was obtained from hospital medical records by six trained medical students. Some information could not be obtained from the hospital medical records. Thus the second step in data collection was the tracking of all the selected subjects to their referring neighborhood health centers. For the analysis, the data were divided into 3 case (outcome) categories: 453 subjects were the total case group. From these, 153 were the IUGR case group and 300 were the LBW preterm case group. The general control group consisted of 605 normal birthweight infants. 565 were the IUGR control group and 40 were the preterm control group. A total of 25 risk factors showed a significant crude odds ratio for at least one of the groups. In the multivariate logistic regression analysis eight variables: No. of pregnancies, previous adverse outcomes, previous LBW, pregnancy maternal weight, No. of visits, month of first prenatal care visit, maternal smoking and intrahepatic cholestasis of pregnancy, were significantly associated with LBW after adjustment by confounding. Eight risk factors: IUGR in previous pregnancies, Previous adverse outcome, Maternal smoking, intrahepatic cholestasis, maternal pregnancy weight, maternal height, month first prenatal visit, No. of visit, were significant to IUGR. Only two variables: pregnancy weight, divorced mother, were significantly associated with low birth weight in the preterm group. The most relevant risk factors were included in stepwise logistic regression models carried out for the outcome LBW for the general group, term group and preterm group, in order to adjust by confounding. Adjusted odds ratios were then obtained. Prenatal care related factors and maternal adverse obstetric factors were at higher significance for LBW in the general and IUGR groups. Only nutritional factors were related to LBW in preterm group. Women who delivered a LBW or IUGR infant were more likely to have fewer pregnancies, a history of previous LBW, lower prepregnancy weight and lower gestational weight gain. ICP was associated with an elevated risk of LBW that was independent of gestational age.