Blood feeding patterns of Nyssomyia intermedia and Nyssomyia neivai (Diptera, Psychodidae) in a cutaneous leishmaniasis endemic area of the Ribeira Valley, State of São Paulo, Brazil

Introduction The aim of this study was to identify the blood feeding sources of Nyssomyia intermedia (Ny. intermedia) and Nyssomyia neivai (Ny. neivai), which are Leishmania vectors and the predominant sandfly species in the Ribeira Valley, State of São Paulo, Brazil, an endemic area for cutaneous leishmaniasis. Methods Specimens were captured monthly between February 2001 and December 2003 on a smallholding and a small farm situated in the Serra district in the Iporanga municipality. The blood meals of 988 engorged females were tested using the avidin-biotin immunoenzymatic enzyme-linked immunosorbent assay (ELISA). Seven blood meal sources were investigated: human, dog, chicken, bovine, pig, horse and rat. Results The results showed that among the females that fed on one or more blood sources, the respective percentages for Ny. intermedia and Ny. neivai, respectively, were as follows: human (23% and 36.8%), pig (47.4% and 26.4%), chicken (25.7% and 36.8%) and dog (3.9% and 0%), and the differences in the blood sources between the two species were statistically significant (p = 0.043). Conclusions Both species had predominant reactivity for one or two blood sources, and few showed reactivity indicating three or four sources. Many different combinations were observed among the females that showed reactivity for more than one source, which indicated their opportunistic habits and eclecticism regarding anthropic environmental conditions.

Histological study of capuchin monkey (Cebus apella) ovarian follicles

The present study aimed to obtain quanti-qualitative data about the follicular ovarian population in Cebus apella females. Seven ovaries were obtained from 4 C. apella adult females. The ovaries were subjected to light microscopy. The number of preantral and antral follicles for each ovary was estimated using the Fractionator method. The preantral follicles were classified into primordial, transitional, primary and secondary follicles. Antral follicles were those that presented an antral cavity. All counted follicles were classified as normal or degenerated. The diameter of the follicles, oocytes and their nuclei were determined to accompany the follicular development. All results were represented as mean ± SE. The number of preantral follicles was 56,938 ± 21,888 and 49,133 ± 26,896 for the right and left ovaries, respectively. The percentage of normal follicles was 80 ± 4.95%. The follicular diameter ranged from 22 ± 0.5 µm to 61.2 ± 4.0 µm. Regarding the antral follicles, the number of normal and degenerate follicles per ovary were 60.0 ± 19.0 and 3 ± 1.8 follicles, respectively. The antral follicular diameter was 514.4 + 56.6 µm. In conclusion, the information obtained in this study can be used as a parameter for subsequent in vivo or in vitro studies about folliculogenesis in non-human neotropical primates of the C. apella species.

Assessment of a protease inhibitor peptide for anti-ageing

Ageing and skin exposure to UV radiation induces production and activation of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE). These enzymes are known to break down the extracellular matrix (ECM) which leads to wrinkle formation. Here, we demonstrated the potential of a solid-in-oil nanodispersion containing a competitive inhibitor peptide of HNE mixed with hyaluronic acid (HA), displaying 158 nm of mean diameter, to protect the skin against the ageing effects. Western blot analysis demonstrated that activation of MMP-1 in fibroblasts by HNE treatment is inhibited by the solid-in-oil nanodispersion containing the peptide and HA. The results clearly demonstrate that solid-in-oil nanodispersion containing the HNE inhibitor peptide is a promising strategy for anti-ageing effects. This effect can be seen particularly by ECM regulation by affecting fibroblasts. The formulation also enhances the formation of thicker bundles of actin filaments.

Reproductive biology of Ameerega trivittata (Anura: Dendrobatidae) in an area of terra firme forest in eastern Amazonia

The reproductive success of tropical amphibians is influenced by factors such as body size and the characteristics of breeding sites. Data on reproductive biology are important for the understanding of population dynamics and the maintenance of species. The objectives of the present study were to examine the abundance of Ameerega trivittata, analyze the use of microhabitats by calling males and the snout-vent length (SVL) of breeding males and females, the number of tadpoles carried by the males and mature oocytes in the females, as well as the relationship between the SVL of the female and both the number and mean size of the mature oocytes found in the ovaries. Three field trips were conducted between January and September, 2009. A total of 31 plots, with a mean area of 2.3 ha, were surveyed, resulting in records of 235 individuals, with a mean density of 3.26 individuals per hectare. Overall, 66.1% of the individuals sighted were located in the leaf litter, while 17.4% were perched on decaying tree trunks on the forest floor, 15.7% on the aerial roots of Cecropia trees, and 0.8% on lianas. Males were observed transporting a mean of 10.8 tadpoles on their backs. A significant correlation was found between the size of the females and the mean diameter of the oocytes. New data were collected on the size of oocytes and no pattern was found in the type of perches used by calling males of the different Ameerega species.

Development of elastin-like recombinamer films with antimicrobial activity

In the present work we explored the ABP-CM4 peptide properties from Bombyx mori for the creation of biopolymers with broad antimicrobial activity. An antimicrobial recombinant protein-based polymer (rPBP) was designed by cloning the DNA sequence coding for ABP-CM4 in frame with the N-terminus of the elastin-like recombinamer consisting of 200 repetitions of the pentamer VPAVG, here named A200. The new rPBP, named CM4-A200, was purified via a simplified nonchromatographic method, making use of the thermoresponsive behavior of the A200 polymer. ABP-CM4 peptide was also purified through the incorporation of a formic acid cleavage site between the peptide and the A200 sequence. In soluble state the antimicrobial activity of both CM4-A200 polymer and ABP-CM4 peptide was poorly effective. However, when the CM4-A200 polymer was processed into free-standing films high antimicrobial activity against Gram-positive and Gram-negative bacteria, yeasts and filamentous fungi was observed. The antimicrobial activity of CM4-A200 was dependent on the physical contact of cells with the film surface. Furthermore, CM4-A200 films did not reveal a cytotoxic effect against both normal human skin fibroblasts and human keratinocytes. Finally, we have developed an optimized ex vivo assay with pig skin demonstrating the antimicrobial properties of the CM4-A200 cast films for skin applications.

Biodegradable drug-eluting stents: Targeting urothelial tumors of upper urinary tract

INTRODUCTION & OBJECTIVES: Urothelial tumors of upper urinary tract are ranked among the most common types of cancers worldwide. The current standard therapy to prevent recurrence is intravesical Bacillus Calmetteâ Guerin (BCG) immunotherapy, but it presents several disadvantages such as BCG failure and intolerance. Another way is to use chemotherapy, which is generally better tolerated that BCG. In this case, drugs such as epirubicin, doxorubicin, paclitaxel and gemcitabine are used. Nevertheless, intravesical chemotherapy only prevents recurrence in the short-term. These failings can be partially attributed to the short residence time and low bioavailability of the drug within the upper urinary tract and the cancer cells, resulting in a need for frequent drug instillation. To avoid these problems, biodegradable ureteral stents impregnated by supercritical fluid CO2 (SCF) with each of the four anti-cancer drugs were produced. MATERIAL & METHODS: Four formulations with different concentrations of gelatin and alginate and crosslink agent were tested and bismuth was added to confer radiopaque properties to the stent. The preliminary in vivo validation studies in female domestic pigs was conducted at the University of Minho, Braga, after formal approval by the institutionâ s review board and in accordance with its internal ethical protocol for animal experiments. Paclitaxel, epirubicin, doxorubicin and gemcitabine were impregnated in the stents and the release kinetics was measured in artificial urine solution (AUS) for 9 days by UV spectroscopy in a microplate reader. The anti-tumoral effect of the developed stents in transitional cell carcinoma (TCC) and HUVEC primary cells, used as control, was evaluated. RESULTS: The in vivo validation of this second-generation of ureteral stents performed was herein demonstrated. Biodegradable ureteral stents were placed in the ureters of a female pigs, following the normal surgical procedure. The animals remained asymptomatic, with normal urine flow. The in vitro release study in AUS of the stent impregnated showed a higher release in the first 72h for the four anti-cancer drugs impregnated after this time the plateau was achieved and the stent degraded after 9 days. The direct and indirect contact of the anti-cancer biodegradable stents with the TCC and HUVEC cell lines confirm the anti-tumor effect of the stents impregnated with the four anti-cancer drugs, reducing around 75% of the viability of the TCC cell line after 72h and no killing effect in the HUVEC cells. CONCLUSIONS: The use of biodegradable ureteral stent in urology clinical practice not only reduce the stent-related symptoms but also open new treatment therapyâ s, like in urothelial tumors of upper urinary tract. Furthermore, we have demonstrated the clinical validation in vivo pig model. This study has thus shown the killing efficacy of the anti-cancer drug eluting biodegradable stents in vitro for the TCC cell line, with no toxicity observed in the control, non-cancerous cells.The direct and indirect contact of the anti-cancer biodegradable stents with the TCC and HUVEC cell lines confirm the anti-tumor effect of the stents impregnated with the four anti-cancer drugs, reducing around 75% of the viability of the TCC cell line after 72h and no killing effect in the HUVEC cells. This study has thus shown the killing efficacy of the anti-cancer drug eluting biodegradable stents in vitro for the TCC cell line, with no toxicity observed in the control, non-cancerous cells.

Asfixia perinatal e problemas cardíacos

OBJETIVO: Avaliar a gravidade das complicações cardíacas na asfixia neonatal, sua evolução e correlacioná-las com o grau e duração do processo hipóxico. MÉTODOS: Foram estudados 90 bebês nos últimos 7 anos com grau de Apgar <6 no 5°min de vida. Pelo protocolo, após o exame físico e os cuidados intensivos, eram submetidos a dosagem do pH arterial, CPK-MB, DHL, glicemia, além da realização de radiografia de tórax, eletrocardiograma (ECG), ecocardiograma, seriados e repetidos a cada semana. Aqueles que faleceram eram levados à necropsia. RESULTADOS: Dos 90, 73 (81%) eram prematuros, 30 (41%) eram apropriados para a idade gestacional (AIG) e 43 (59%) eram pequenos(PIG). Em 21 (23%) casos havia pH arterial <7,2. Os quadros clínicos mais observados foram: pneumonia em 28 (31%), anemia 24 (26%) e icterícia moderada 12 (5%), entre outros. Ao exame físico observaram-se: sopro sistólico em 46 (50%), ictus propulsivo 18 (20%) e ICC em 8 (9%). No ECG, os sinais mais freqüentes foram alterações de repolarização (ST e T) em 44 (49%). No ecocardiograma, observou-se persistência do canal arterial (PCA) em 20 (22%), regurgitação tricúspide em 6 (7%), hipertensão pulmonar em 6 (8%), hipocontratilidade de VE e dilatação de VD em 4 (5%). Dos 23 óbitos, 14 foram estudados e as alterações mais freqüentes foram necrose de fibras em 8 (68%) casos e em 4 (29%) congestão, vacuolização e perda de estriação. CONCLUSÃO: A maioria teve evolução favorável mesmo naqueles que tiveram acidemia importante. Muitas alterações de ECG e ecocardiograma se normalizaram. Daqueles que evoluíram para o óbito, as lesões mais graves ocorreram nos que sofreram, por mais tempo, processo anóxico.

Mecanismo de interacción, calcio dependiente, entre Calcineurina y PERK, involucrado en el Estrés de Retículo Endoplásmico. Ca2+ -dependent mechanism of interaction between Calcineurin and PERK involved in Endoplasmic Reticulum Stress.

El Estrés de Retículo Endoplásmico (RE) es inducido por la acumulación de proteínas sin plegar en el lumen de la organela. Esto se puede observar en diversas situaciones fisio-patológicas como durante una infección viral o en proceso isquémico. Además, contribuye a la base molecular de numerosas enfermedades ya sea índole metabólico (Fibrosis quística o Diabetes Miellitus) o neurodegenerativas como mal de Alzheimer o Parkinson (Mutat Res, 2005, 569). Para restablecer la homeostasis en la organela se activa una señal de transducción (UPR), cuya respuesta inmediata es la atenuación de la síntesis de proteína debido a la fosforilación de subunidad alpha del factor eucariótico de iniciación de translación (eIF2α) vía PERK. Esta es una proteína de membrana de RE que detecta estrés. Bajo condiciones normales, PERK está inactiva debido a la asociación de su dominio luminar con la chaperona BIP (Nat Cell Biol, 2000, 2: 326). Frente a una situación de estrés, la chaperona se disocia causando desinhibición. Recientemente, (Plos One 5: e11925) se observó, bajo condiciones de estrés, un aumento de Ca2+ citosólico y un rápido incremento de la expresión de calcineurina (CN), una fosfatasa citosólica dependiente de calcio, heterodimérica formada por una subunidad catalítica (CN-A) y una regulatoria (CN-B). Además, CN interacciona, sin intermediarios, con el dominio citosólico de PERK favoreciendo su trans-autofosforilación. Resultados preliminares indican que, astrocitos CNAβ-/- exhibieron, en condiciones basales, un mayor número de células muertas y de niveles de eIF2α fosforilado que los astrocitos CNAα-/-. Hipótesis: CNAβ/B interacciona con PERK cuando el Ca2+ citosólico esta incrementado luego de haberse inducido Estrés de RE, lo cual promueve dimerización y auto-fosforilación de la quinasa, acentuándose así la fosforilación de eIF2α e inhibición de la síntesis de proteínas. Esta activación citosólica de PERK colaboraría con la ya descrita, desinhibición luminal llevada cabo por BIP. Cuando el Ca2+ citosólico retorna a los niveles basales, PERK fosforila a CN, reduciendo su afinidad de unión y disociándose el complejo CN/PERK. Objetivo general: Definir las condiciones por las cuales CN interacciona con PERK y regula la fosforilación de eIF2α e inhibición de la síntesis de proteína. Objetivos específicos: I-Estudiar la diferencia de afinidades y dependencia de Ca2+, de las dos isoformas de CN (α y β) en su asociación con PERK. Además verificar la posible participación de la subunidad B de CN en esta interacción. II-Determinar si la auto-fosforilación de PERK es diferencialmente regulada por las dos isoformas de CN. III-Discernir la relación del estado de fosforilación de CN con su unión a PERK. IV-Determinar efectos fisiológicos de la interacción de CN-PERK durante la respuesta de Estrés de RE. Para llevar a cabo este proyecto se realizarán experimentos de biología molecular, interacción proteína-proteína, ensayos de fosforilación in vitro y un perfil de polisoma con astrocitos CNAβ-/- , CNA-/- y astrocitos controles. Se espera encontrar una mayor afinidad de unión a PERK de la isoforma β de CN y en condiciones donde la concentración de Ca2+ sea del orden micromolar e imite niveles del ión durante un estrés. Con respecto al estado de fosforilación de CN, debido a los resultados preliminares, donde solo se la encontró fosforilada en condiciones basales, se piensa que CN podría interactuar con mayor afinidad con PERK cuando CN se encuentre desfosforilada. Por último, se espera encontrar un aumento de eIF2α fosforilado y una acentuación de la atenuación de la síntesis de proteína como consecuencia de la mayor activación de PERK por su asociación con la isoforma β de CN en astrocitos donde el Estrés de RE se indujo por privación de oxigeno y glucosa. Estos experimentos permitirán avanzar en el estudio de una nueva función citoprotectora de CN recientemente descrita por nuestro grupo de trabajo y sus implicancias en un modelo de isquemia. The accumulation of unfolded proteins into the Endoplasmic Reticulum (ER) activates a signal transduction cascade called Unfolding Protein Response (UPR), which attempts to restore homeostasis in the organelle. (PKR)-like-ER kinase (PERK) is an early stress response transmembrane protein that is generally inactive due to its association with the chaperone BIP. During ER stress, BIP is tritrated by the unfolded protein, leading PERK activation and phosphorylation of eukaryotic initiation factor-2 alpha (eIF2alpha), which attenuates protein síntesis. If ER damage is too great and homeostasis is not restored within a certain period of time, an apoptotic response is elicited. We recently demonstrated a cytosolic Ca2+ increase in Xenopus oocytes after induce ER stress. Moreover, calcineurin A/B, a an heterotrimeric Ca2+ dependent phosphatases (CN-A/B), associates with PERK increasing its auto-phosphorylation and significantly enhancing cell viability. Preliminary results suggest that, CN-Aβ-/- knockout astrocytes exhibit a significant higher eIF2α phosphorylated level compared to CN-Aα-/- astrocytes. Our working hypothesis establishes that: CN binds to PERK when cytosolic Ca2+ is initially increased by ER stress, promoting dimerization and autophosphorylation, which leads to phosphorylation of elF2α and subsequently attenuation of protein translation. When cytosolic Ca2+ returns to resting levels, PERK phosphorylates CN, reducing its binding affinity so that the CN/PERK complex dissociates. The goal of this project is to determine the conditions by which CN binding to PERK attenuates protein translation during the ER stress response and subsequently, to determine how the interaction of CN with PERK is terminated when stress is removed. To perform this project is planed to do molecular biology experiments, pull down assays, in vitro phosphorylations and assess overall mRNA translation efficiency doing a polisome profile.

Aspectos bioquímicos y celulares de la reproducción de los vectores de la enfermedad de Chagas: regulación e importancia fisiológica. Biochemical and cellular aspects of the reproduction of Chagas’ disease vectors: regulation and physiologycal impact

En la hipótesis de trabajo del presente proyecto se considera la importancia del metabolismo de lípidos y proteínas en los insectos hematófagos, en particular en los vectores de la enfermedad de Chagas, para afrontar exitosamente la demanda energética de la reproducción. Las hembras de estas especies pueden ingerir una comida de sangre abundante en lípidos y proteínas, los que son modificados en el intestino para su utilización y posterior almacenamiento en estructuras organizadas en el tejido ovárico, sustentando así el rápido crecimiento de los ovocitos. Estos aspectos resultan críticos para el ciclo de vida del insecto y para el mantenimiento de la cadena epidemiológica de la enfermedad. En estas especies, recientemente hemos caracterizado a nivel bioquímico y celular la interacción entre lipoproteínas y tejidos [Fruttero y col., Insect Biochem. Mol. Biol. 39: 322-331 (2009); Fruttero y col. Biocel 33 (3): 260 (2009)] y las fases del ciclo reproductivo [Aguirre y col., J. Insect Physiol. 54: 393-402 (2008)]. No obstante, los factores que participan en su regulación son aún escasamente conocidos. En este contexto, el estudio propone emplear dos especies de triatominos con el objeto de: (1) caracterizar los factores involucrados en la formación y regulación de reservas nutricionales en los ovocitos; (2) analizar los eventos que participan en la regresión del tejido ovárico: atresia folicular y mecanismos de muerte celular. (3) evaluar el impacto de productos naturales (ureasas vegetales y péptidos derivados) en el desarrollo del tejido ovárico. Para la ejecución de los objetivos se llevarán a cabo ensayos in vivo e in vitro con trazadores fluorescentes, fraccionamiento subcelular, estudios de expresión de proteínas (mRNA y proteína), estudios histo-morfológicos, ultraestructurales e inmunocitoquímicos, microscopía láser confocalizada, ensayos de actividad enzimática, ELISA, western-blot, electroforesis bidimensional, espectrometria de masas en tándem, etc. También se evaluarán los mecanismos de muerte celular (apoptosis/autofagia) mediante microscopía electrónica, detección de apoptosis in situ (TUNEL), inmunofluorescencia, etc. Los resultados obtenidos permitirán un mejor conocimiento sobre la fisiología y bioquímica de estos vectores, los que resultan indispensables en el diseño de nuevas estrategias para su control. Debido a la carencia de un tratamiento específico para la enfermedad y a la falta de métodos preventivos (vacuna), el control del vector es una de las vías más importantes para reducir la incidencia de la enfermedad. Actualmente, la situación socio-económica que sufren amplios núcleos de nuestra población propicia condiciones de vida que facilitan la reproducción de los vectores y la transmisión vectorial del parásito. El estudio permitirá además explorar aspectos bioquímicos y celulares básicos, generando conocimientos que podrían ser extensivos a otros insectos de importancia económica en la ganadería y/o agricultura. The aim of this project is to analyze the biochemical and cellular events involved in the lipid and protein metabolism in Chagas' disease vectors, and to evaluate their impact on the physiology of reproduction, particularly in the formation of nutritional resources in developing oocytes. At present, little is known about these critical aspects for the life cycle of the insect and for the epidemiology of the disease. The experimental approaches, which will be carried out using two species of triatomines, were designed: (1) to characterize factors involved in the formation and regulation of nutritional resources in developing oocytes; (2) to analyze the biochemical and cellular events that play a role during the regression of ovarian tissue, including the processes of oocyte resorption and programmed cell death. (3) to evaluate the impact of natural products (ureases from jackbean and related peptides) in the development of ovarian tissue. Methods and techniques involved in the project are: in vivo and in vitro assays with fluorescent tracers, ELISA, chemical assays, enzyme activities, western-blot; protein expression (mRNA), histological techniques, immunohistochemical and ultrastructural studies. Cell death will be analyzed by detection of apoptosis in situ (TUNEL), immunofluorescence (for autophagy), among others. The results obtained from the study will offer the opportunity to explore important aspects in the biology and physiology of Chagas' disease vectors that could be of potential utility in designing alternative strategies for the control of the insect.

A nutrient balance model for typical Irish farming systems

The twin objectives of the work described were to construct nutrient balance models (NBM) for a range of Irish animal production systems and to evaluate their potential as a means of estimating the nutrient composition of farm wastes. The NBM has three components. The first is the intake of nutrients in the animal's diet. The second is retention or the nutrients the animal retains for the production of milk, meat or eggs. The third is the balance or the difference between the nutrient intake and retention. Data on the intake levels and their nutrient value for dairy cows, beef cattle, pigs and poultry systems were assembled. Literature searches and interviews with National experts were the primary sources of information. NBMs were then constructed for each production system. Summary tables of the nutrient values for the common diet constituents used in Irish animal production systems, the nutrient composition of the animal products and the NBMs (nutrient intake, retention and excretion) for a range of production systems were assembled. These represent the first comprehensive data set of this type for Irish animal production systems. There was generally good agreement between the derived NBMs values and those published in the literature. The NBMs were validated on a number of farms. Data on animal numbers, fertiliser use, concentrates inputs and production output were recorded on seven farms. Using the data a nutrient input/output balance was constructed for each farm. This was compared with the NBM estimate of the farm nutrient balance. The results showed good agreement between the measured balance and the NBM estimate particularly for the pig and poultry farms. However, the validation emphasised the inherent risks associated with NBMs. The average values used for feed intake and production parameters in the NEMs may result in the under or over estimate of actual nutrient balances on individual farms where these variables are substantially different. On the grassland farms there was a poor correlation between the input/output estimate and the NBM. This possibly results from the omission of the soil's contribution to the nutrient balance. However, the results indicate that the NBMs developed are a potentially useful tool for estimating nutrient balances. They also will serve to highlight the significant fraction of the nutrient inputs into farming systems that are retained on the farm. The potential of the NBM as a means of estimating the nutrient composition of farm wastes was evaluated on two farms. Feed intake and composition, animal production, slurry production was monitored during the indoor winter feeding period. Slurry samples were taken for analysis. The appropriates NBMs were used to estimate the nutrient balance for each farm. The nutrient content of the slurry produced was calculated. There was a good agreement between the NBM estimate and the measured values. This preliminary evaluation suggests that the NBM has a potential to provide the farmer with a simple means of estimating the nutrient value of his slurry.

Biologia reprodutiva de Apidoras fuscoguttatus (Siluriformes, Callichthyidae) em riacho de cabeceira da bacia do alto Rio Paraná

The reproductive biology of Aspidoras fuscoguttatus Nijssen & Isbrücker, 1976 from a stream in São José do Rio Preto, northwestern São Paulo State, Brazil, was monthly investigated in the period of August 1999 to July 2000. Measurements of total length, body weight, gonadal weight and macroscopic assessment of gonadal maturation were performed. Environmental parameters were considered in order to verify associations with the reproductive period. Populational structure showed total length amplitude between 14.2 and 50.8 mm. Pronounced sexual dimorphism was verified. The largest mean values of gonadosomatic relation for females coincided with the rainy season (November to March). Mean length at first sexual maturity was different for males (30.5 mm) and females (37.1 mm). Fecundity varied between 51 and 166 oocytes. Gonadal maturation curve, frequency of maturation stages and size frequency distributions of oocytes in mature ovaries revealed a long reproductive period, suggesting fractional spawning.

Taxonomy and evolution of liontail and pigtail macaques (Primates : Cercopithecidae) / Jack Fooden.

v.67(1975)

Dinâmica reprodutiva de Oligosarcus jenynsii e O. robustus (Characiformes, Characidae) na lagoa Fortaleza, Rio Grande do Sul, Brasil

Oligosarcus jenynsii (Günther, 1864) and O. robustus Menezes, 1969 are fish species distributed in Rio Grande do Sul, Brazil, Uruguay, and northern Argentina. The reproductive period and recruitment, sex ratio, absolute and relative fecundity, and body length at first gonadal maturation of the two carnivorous species from Fortaleza Lagoon were analized. The specimens were sampled monthly, from May 2000 to April 2001, with fishing effort of 24 hours/month, using stationary gillnets of different mesh sizes and seine net (three samples per edge). The records of each individual included total length, total weight, gonad weight, sex and gonadal maturity stage. The reproductive period of both O. jenynsii and O. robustus ranges from May/June to November/December, according to the bimonthly variation of the mean values of gonosomatic index, and the relative frequencies of the gonadal maturation stages. Recruitment of new individuals to the population occurs from November/December to March/April. The sex ratio is different from 1:1 for O. jenynsii and similar to 1:1 for O. robustus. The mean absolute fecundity, calculated by counting sub-sampled oocytes from mature females, was 14,483 oocytes for O. jenynsii, and 16,308 oocytes for O. robustus. The first maturation curve shows that O. jenynsii begins to reproduce between 84 mm and 104 mm (total length), and O. robustus between 126 mm and 146 mm, probably at similar ages.

Gonad development in females of fiddler crab Uca rapax (Crustacea, Brachyura, Ocypodidae) using macro and microscopic techniques

The morphology of the ovaries in Uca rapax (Smith, 1870) was described based on macroscopic and microscopic analysis. Females were collected in Itamambuca mangrove, Ubatuba, state of São Paulo, Brazil. In the laboratory, 18 females had their ovaries removed and prepared for histology. Each gonad developmental stage was previously determined based on external and macroscopic morphology and afterwards each stage was microscopically described. The ovaries of U. rapax showed a pronounced macroscopic differentiation in size and coloration with the maturation of the gonad, with six ovarian developmental stages: immature, rudimentary, developing, developed, advanced and spent. During the vitellogenesis, the amount of oocytes in secondary stage increases in the ovary, resulting in a change in coloration of the gonad. Oogonias, primary oocytes, secondary oocytes and follicular cells were histologically described and measured. In female’s ovaries of U. rapax the modifications observed in the oocytes during the process of gonad maturation are similar to descriptions of gonads of other females of brachyuran crustaceans. The similarities are specially found in the morphological changes in the reproductive cells, and also in the presence and arrange of follicle cells during the process of ovary maturation. When external morphological characteristics of the gonads were compared to histological descriptions, it was possible to observe modifications that characterize the process in different developmental stages throughout the ovarian cycle and, consequently, the macroscopic classification of gonad stages agree with the modifications of the reproductive cells.

Advertisement call and female sexual cycle in Uruguayan populations of Physalaemus henselii (Anura, Leiuperidae)

Physalaemus henselii (Peters, 1872) is a little known leiuperid frog that has not been studied since the 1960’s. Herein, we redescribe its advertisement call, and assess the female sexual cycle and the reproductive period on the basis of the macroscopic analysis of the ovaries and field observations. The Ovarian Size Factor (OSF) was calculated. The study was made in Departamento de Rivera, northern Uruguay. The advertisement call consists of short (177 ± 21ms), multipulsed (20 ± 3 pulses/note) notes, with a note repetition rate of 1.57 ± 0.13 notes/s. Physalaemus henselii has a female sexual cycle with unimodal distribution of gravid females, which are present from February to September. The OSF and the ratio "females with mature oocytes / females without mature oocytes" reached the highest values from April to June. The number and size of oocytes were positively correlated with female size. The smallest female (SVL =18.94mm, weight =0.78g) with mature oocytes was found in July. The observed sexual cycle with a single annual reproductive period during the cold season (autumn and early winter), is an uncommon fact for anuran species in the region.