Protandry and female size-fecundity variation in the tropical butterfly Brassolis sophorae

Protandry (the emergence of males before fe males) is currently explained either as a mating strategy to maximize number of matings in the males, or a way to minimize pre-reproductive mortality in females, Models of protandry have generally ignored variation in female quality (reproductive potential). We recorded the sex ratio, female body mass, wing length and potential fecundity (number and mass of eggs) of the tropical butterfly Brassolis sophorae through the emergence period. Temporal variation in female size and fecundity correlated with male potential for acquiring mates. Females from the end of the emergence period showed lower fecundity and size. Males emerging before and close to the median date of the female emergence period had greater mating opportunities. Males emerging either very early or late were penalized by few mating opportunities, or by encounters with small: low-quality females, respectively.

Hemiodus jatuarana, a new species of Hemiodontidae from the rio Trombetas, Amazon Basin, Brazil (Teleostei, Characiformes)

Hemiodus jatuarana, a new species of the Hemiodontidae from Oriximina, rio Trombetas, Amazon Basin, Brazil, is described. The new species can be readily distinguished from its congeners by the presence of a horizontally elongated dark spot on the caudal peduncle, and by the absence of any other dark pigmentation pattern on the body. Hemiodus jatuarana is readily separated from H. immaculatus, another species without dark pigmentation on the body, by having 25 - 27 epibranchial and 36 - 37 ceratobranchial gill rakers on the first branchial arch, and caudal-fin lobes without longitudinal stripes, vs. 14 - 16 and 21 - 25 gill rakers, and a conspicuous longitudinal stripe on each caudalfin lobe in H. immaculatus. The new species is only known from its type-locality, where it cooccurs with H. immaculatus.

Four new species of Bacilloflagellomera Papp & Silva, 1995 (Diptera, Lauxaniidae)

Four new species of the Neotropical Lauxaniidae genus Bacilloflagellomera Papp & Silva, 1995 (Diptera, Lauxaniidae) from Brazil are described: B. flava sp. n, (Para, Belem); B. fusca sp. n. (São Paulo, Aracatuba), B. longicornus sp. n. (Amapa, Serra do Navio) and B. nigrifemuris sp. n. (Para, Belem). A key for the identification of the species, illustrations of head, wing and terminalia of the new species are provided. A short discussion on the structure and systematic value of the inner morphology of female terminalia is included.

HMB-45 - A review

HMB-45, named for the immunogen used (human melanoma, black) is a monoclonal antibody developed 10 years ago by Gown and colleagues to a whole-cell extract of a human melanoma. Over the years, it has been demonstrated that HMB-45 is a highly sensitive and specific reagent for the identification of melanoma. More recently, it has been found that HMB-45 reacts with a protein designated gp100-cl, which is apparently related to the pmel 17 gene product. Because gp100-cl is a melanosomal matrix protein, HMB-45 is more correctly identified as an organelle-specific rather than tumor-specific reagent. HMB-45 immunoreactivity is seen in normal fetal and neonatal melanocytes but not in adult resting melanocytes. Reactive or proliferating melanocytes present in inflamed adult skin or in skin overlying certain dermal neoplasms, can also ''re-express'' the HMB-45-defined antigen. Whereas the vast majority of melanomas are HMB-45-positive, one important exception is desmoplastic malignant melanoma, which consistently demonstrates a much lower rate of expression of the HMB-45-defined antigen compared with other types of melanoma. In recent years there have been scattered reports of HMB-45 immunoreactivity in nonmelanomatous tumors, such as breast and other carcinomas, but virtually all these reports employed commercial ascites fluid preparations of HMB-45 antibody that were subsequently shown to be contaminated with nonspecific antibodies. Thus, for most practical purposes, a positive reaction with HMB-45 indicates active melanosome formation and, therefore, melanocytic differentiation. There is also a set of HMB-45-positive tumors that consistently manifest HMB-45 immunoreactivity but do not display obvious pigmentation: clear cell ''sugar'' tumor of the lung, angiomyolipoma, and lymphangiomyomatosis. Nonetheless, these lesions are all unified by recent ultrastructural studies that confirm the presence premelanosomes. Curiously, all three lesions also manifest evidence for simultaneous smooth-muscle differentiation. HMB-45 remains, therefore, a reliable marker of melanoma but may also provide insights into a rare group of tumors.

Structural and functional characterization of myotoxin I, a Lys49 phospholipase A(2) homologue from Bothrops moojeni (Caissaca) snake venom

Myotoxin-I (MjTX-I) was purified to homogeneity from the venom of Bothrops moojeni by ion-exchange chromatography on CM-Sepharose. Its molecular weight, estimated by SDS-PAGE, was 13,400 (reduced) or 26,000 (unreduced). The extinction coefficient (E-1.0 cm(1.0 mg/ml)) of MjTX-I was 1.145 at lambda = 278 nm, pH 7.0, and its isoelectric point was 8.2 at ionic strength mu = 0.1. When lyophilized and stored at 4 degrees C, dimeric, trimeric, and pentameric forms of the protein were identified by SDS-PAGE. This heterogeneous sample could be separated into three fractions by gel filtration on Sephadex 6-50. The fractions were analyzed by isoelectric focusing, immunoelectrophoresis, and amino acid composition, which indicated that heterogeneity was the result of different levels of self-association. Protein sequencing indicated that MjTX-I is a Lys49 myotoxin and consists of 121 amino acids (M-r = 13,669), containing a high proportion of basic and hydrophobic residues. It shares a high degree of sequence identity with other Lys49 PLA(2)-like myotoxins, but shows a significantly lower identity with catalytically active Asp49 PLA(2)s. The three-dimensional structure of MjTX-I was modeled based on the crystal structures of three highly homologous Lys49 PLA(2)-like myotoxins. This model showed that the amino acid substitutions are conservative, and mainly the beta-wing region, and the C-terminal extended random coil. MjTX-I displays local myotoxic and edema-inducing activities in mice, and is lethal by intraperitoneal injection, with an LD50 value of 8.5 +/- 0.8 mg/kg, In addition, it is cytotoxic to myoblasts/ myotubes in culture, and disrupts negatively charged liposomes. In comparison with the freshly prepared dimeric sample, the more aggregated forms showed significantly reduced myotoxic activity. However, the edema-inducing activity of MjTX-I was independent of molecular association. Phospholipase A(2) activity on egg yolk, as well as anticoagulant activity, were undetectable both in the native and in the more associated forms. His, Tyr, and Trp residues of the toxin were chemically modified by specific reagents. Although the myotoxic and lethal activities of the modified toxins were reduced by these treatments, neither its edema-inducing or Liposome-disrupting activities were significantly altered. Rabbit antibodies to native MjTX-I cross-reacted with the chemically modified forms, and both the native and modified MjTX-I preparations were recognized by antibodies against the C-terminal region 115-129 of myotoxin II from B. asper, a highly Lys49 PLA(2)-homologue with high sequencial similarity. (C) 2000 Academic Press.

Radiative properties of the skin and haircoat of cattle and other animals

Radiative properties (reflectance rho, transmittance tau, and absorptance alpha) were determined for wavelengths from 300 to 850 nm in the haircoat and the skin of water buffalo, deer (Pantanal deer, Blastocerus dichotomus), and cattle of the Holstein, Simmental, Canchim, Brangus, and Nelore breeds. The results showed that white hairs have higher rho (0.60 to 0.67) than the other coat colors, but the gray coats (mixed white and dark hair) of the Nelore cattle presented higher rho than that of the white coats of the European breeds at wavelengths lower than 600 nm. The light gray colored skin of the Canchim cattle had higher rho (0. 66) than the non-pigmented skin of Holstein (0.53). Red skins presented rho values higher than those of dark gray and black skins. Buffalo skin (dark gray) presented an average rho of 0.23+/-0.02 and alpha of 0.77+/-0.02. The red haircoat of the deer presented rho lower (0.37) than that of cattle of the same color (0.58). However, there was little difference between deer and cattle with respect to reflectance and absorptance of the skin. As for the spectral transmittance of the skin, it was very low and about the same for both species, until 600 nm. In the range 600 to 850 nm, the tau values for cattle rose to 0. 17, while those for deer increased only to 0.12.

Morphology of the nymphoid replacement reproductives in the neotropical termite Armitermes euamignathus (Isoptera, Termitidae, Nasutitermitinae)

Numerous nymphoid reproductives were found in three field nests of Armitermes euamignathus collected in Brazil. We report here a morphological description and a biometric study of these individuals. Nymphoid replacements displayed narrow wing buds when compared with those present in nymphs from the three last instars. Thorax morphology of the nymphoids was similar to the penultimate nymphal instar (N4) or to the ultimate nymphal instar (N5), and their origin from these instars of nymphs is discussed. All the nymphoids had eyes, ocelli, and 15 antennal segments. The nymphoid females from nest 1 had different grades of physogastry and royal fat body. The nymphoid females from nests 2 and 3, the nymphoid males from all nests, and the primary king from nests 2 acid 3 had a common fat body, which is similar to that present in alates. The ovaries and the testes of nymphoids were fully mature and the corpora allata larger than those in imagoes. The mandibular glands were also enlarged in nymphoids but the tergal glands were absent. (C) 1999 Wiley-Liss, Inc.

Induction of the split sting trait in Africanized Apis mellifera (Hymenoptera : Apidae) by cold treatment of pupae

Split sting is the name given to a nonfunctional honey bee sting characterized by lancets not attached to the stylet. It has appeared in a mutant line in Brazil, and has provoked interest as a possible means to reduce honey bee colony defensiveness. We induced this alteration in Africanized Apis mellifera L. workers and queens by maintaining pupae at 20 degrees C. In particular, we determined the pupal phase most susceptible to alterations in the sting caused by cold treatment, and we investigated whether this treatment also affected survival to the adult phase and wing morphology. The highest frequency of split sting was detected in workers treated at the pink-eyed pupal phase. The lowest frequency was observed in the bees treated at the oldest worker pupal phase studied (brown-eyed pupae with lightly pigmented cuticle). Both queen pupal phases tested (white and pink-eyed pupae) were equally sensitive and produced high percentages of adults with split sting. However, the 20 degrees C treatment of workers and queens, at the different pupal phases, resulted in high frequencies of adults with deformed wings. Also, fewer workers and queens treated at the earlier pupal stages reached adult emergence. There was also an arrest in developmental time, corresponding to the period of cold treatment.

Assessment of brachial plexus blockade in chickens by an axillary approach

Objective To assess the brachial plexus block in chickens by an axillary approach and using a peripheral nerve stimulator.Study design Prospective, randomized, double-blinded study.Animals Six, 84-week old, female chickens.Methods Midazolam (1 mg kg(-1)) and butorphanol (1 mg kg(-1)) were administered into the pectoralis muscle. Fifteen minutes later, the birds were positioned in lateral recumbency and following palpation of the anatomic landmarks, a catheter was inserted using an axillary approach to the brachial plexus. Lidocaine or bupivacaine (1 mL kg(-1)) was injected after plexus localization by the nerve stimulator. Sensory function was tested before and after blockade (carpus, radius/ulna, humerus and pectoralis muscle) in the blocked and unblocked wings. The latency to onset of motor and sensory block and the duration of sensory block were recorded. A Friedman nonparametric one-way repeated-measures ANOVA was used to compare scores from baseline values over time and to compare the differences between wings at each time point.Results A total of 18 blocks were performed with a success rate of 66.6% (12/18). The latency for motor block was 2.8 +/- 1.1 and 3.2 +/- 0.4 minutes for lidocaine and bupivacaine, respectively. The latencies for and durations of the sensory block were 6.0 +/- 2.5 and 64.0 +/- 18.0 and 7.8 +/- 5.8 and 91.6 +/- 61.7 minutes for lidocaine and bupivacaine, respectively. There was no statistical difference between these times for lidocaine or bupivacaine. Sensory function was not abolished in nonblocked wings.Conclusions and clinical relevance The brachial plexus block was an easy technique to perform but had a high failure rate. It might be useful for providing anesthesia or postoperative analgesia of the wing in chickens and exotic avian species that have similar wing anatomy.

ARE CORPORAL ALLOMETRIC MEASUREMENTS GOOD PREDICTORS of PALATABILITY IN NEOTROPICAL BUTTERFLIES (LEPIDOPTERA)?

Since palatable butterflies are more dependent on evasive flight to escape from predators, they should be more restricted in their flight-related morphology than unpalatable ones. We compared: the ratios between the (1) length of head plus thorax and the length of abdomen (A/B), (2) length of the tip of the head to wing base and the length of the wing base to end of the abdomen (C/D), (3) the variances of A/B and C/D, (4) the proportion between the thoracic and the body weight, and (5) the flight speed between palatable and unpalatable butterflies. A/B and thoracic/body weight were higher for palatable species, indicating higher body symmetry and muscular mass. However, flight speed did not differ. Unexpectedly, the variance of A/B was higher for palatable species while that of C/D did not differ. Therefore, corporal allometric measurements of Neotropical butterflies are good predictors of palatability, though not of flight speed.

A comparative study of the extracutaneous pigmentary system in three anuran amphibian species evaluated during the breeding season.

The present investigation examined the extracutaneous pigmentation pattern of three species of anuran amphibians, Dendropsophus nanus, Physalaemus cuvieri, and Rhinella schneideri, during the course of their breeding seasons. Pigmentation intensity in the different organs was graded on a 4-category scale, in which category 0 refers to organs without pigment and category 3 refers to intensely pigmented organs, with 2 intermediate stages of progressively stronger pigmentation. Rhinella schneideri showed testicular pigmentation, with intra-specific variation (categories 0 and 1). In P. cuvieri the pigmentation in the lungs varied in time: all the animals showed pigmentation (category 1) at the beginning of the breeding season, and as the season progressed the absence of pigments became the most common pattern. In the liver of the first animals collected, the pigment intensity was high (category 2) with many iridophores present, but in the last specimens collected no iridophores were found. The variation in D. nanus occurred in the kidneys, where animals collected at the beginning of the season did not show pigmentation. Renal veins displayed few melanocytes (category 1); animals collected at the end of the season showed more pigmentation in the kidneys (category 2), whereas in the renal veins the intensity remained the same. The changes observed in the extracutaneous pigment system in some organs, during the reproductive period, may be due to physiological alterations or may represent a species-specific characteristic.

Predicting body and carcass characteristics of 2 broiler chicken strains using support vector regression and neural network models

As a new modeling method, support vector regression (SVR) has been regarded as the state-of-the-art technique for regression and approximation. In this study, the SVR models had been introduced and developed to predict body and carcass-related characteristics of 2 strains of broiler chicken. To evaluate the prediction ability of SVR models, we compared their performance with that of neural network (NN) models. Evaluation of the prediction accuracy of models was based on the R-2, MS error, and bias. The variables of interest as model output were BW, empty BW, carcass, breast, drumstick, thigh, and wing weight in 2 strains of Ross and Cobb chickens based on intake dietary nutrients, including ME (kcal/bird per week), CP, TSAA, and Lys, all as grams per bird per week. A data set composed of 64 measurements taken from each strain were used for this analysis, where 44 data lines were used for model training, whereas the remaining 20 lines were used to test the created models. The results of this study revealed that it is possible to satisfactorily estimate the BW and carcass parts of the broiler chickens via their dietary nutrient intake. Through statistical criteria used to evaluate the performance of the SVR and NN models, the overall results demonstrate that the discussed models can be effective for accurate prediction of the body and carcass-related characteristics investigated here. However, the SVR method achieved better accuracy and generalization than the NN method. This indicates that the new data mining technique (SVR model) can be used as an alternative modeling tool for NN models. However, further reevaluation of this algorithm in the future is suggested.

Geographic variation of Africanized honey bees (Apis mellifera L.) in Brazil: Multivariate morphometrics and racial admixture

The correspondence between morphometric and isozymic geographic variation patterns of Africanized honey bees in Brazil was analyzed. Morphometric data consisted of mean vectors of 19 wing traits measured in 42 local populations distributed throughout the country. Isozymic data refer to allelic frequencies of malate dehydrogenase (MDH), and were obtained from Lobo and Krieger. The two data sets were analyzed through canonical trend surface, principal components and spatial autocorrelation analyses, and showed north-south dines, demonstrating that Africanized honey bees in southern and southeastern Brazil are more similar to European honey bees than those found in northern and northeastern regions. Also, the morphometric variation is within the limits established by the racial admixture model, considering the expected values of Africanized honey bee fore wing length (WL) in southern and northeastern regions of Brazil, estimated by combining average values of WL in the three main subspecies involved in the Africanization process (Apis mellifera scutellata, A. m. ligustica and A. m. mellifera) with racial admixture coefficients.

Response to orphaning in two Neotropical termites: Armitermes euamignathus and Embiratermes festivellus

In this paper we examine the potential of the termites Armitermes euamignathus Silvestri: 1901 and Embiratermes festivellus (Silvestri, 1901) (Isoptera, Termitidae, Nasutitermitinae) to produce neotenics experimentally. Three nests of the mound-building termite A. euamignathus, from the Brazilian cerrado, had their primary queens removed in August 1994. After 12 months, only one mound survived; it had a normal appearance. In this healthy, orphaned colony we found the primary king, six physogastric nymphoid female replacement reproductives, two ergatoid female replacement reproductives, 46 nymphs, several presoldiers, soldiers, workers, larvae and many eggs. These data show that neotenics in A. euamignathus may originate from both workers and nymphs, but nymphoids are produced in larger numbers. The biometric study of nymphs and nymphoids suggests that these brachypterous neotenics were derived from third instar nymphs after a single moult or from four instar nymphs after a reduction of wing bud length. A piece of an E. festivellus nest with some third instar nymphs, soldiers and workers was kept under laboratory conditions. After 12 months, the whole experimental subcolony was examined and appeared to contain two pigmented nymphoid females, two pigmented nymphoid males, only one larva, seven nymphs of the same instar, 148 workers, five soldiers and many eggs. These results also indicate the capacity of the termite E. festivellus to produce nymphoid neotenics. These neotenic females were laying eggs, but they were not physogastric after a year, unlike some nymphoids of the same species collected from natural colonies.

Ácido glicólico: Agente despigmentante e rejuvenescedor

The skin pigmentation caused by ultraviolet light irradiation as a defense against the carcinogenic action of solar light may lead to early skin aging and to hyperchromia, which treatment requires the use of photo-protective, depigmenting and rejuvenating agents. Recently, there have been used many substances for the prevention and/or treatment of skin aging as well as to lowering the skin pigmentation. Glycolic acid is the alpha-hydroxy acid most commonly used in cosmetic and dermatological prepatations. This use is due to its depigmentating and rejuvenating properties and its efficacy at different concentrations, when incorporated to different kind of excipients.