Abstract
We characterized the natural diet and feeding dynamics of Aegla castroSchmitt, 1942 (Aeglidae), an endemic freshwater crab. Research was undertaken on the trophic spectrum of the species by ...analyzing the stomach contents of individuals collected in a stream in southeastern Brazil, and evaluating the diet through the index of relative importance (IRI). Seasonal and circadian variations in diet composition were analyzed, and the feeding dynamics investigated through repletion index (RI) analysis. We analyzed a total of 240 stomachs and identified 20 main food categories of the diet, which were studied throughout the seasons. Aegla castro maintained a constant RI throughout the year, with a peak of food activity between midnight (00) and 0600. The species was characterized as an omnivorous generalist and opportunist. The high overlay in the diet composition of adults of both sexes and juveniles indicates that they share the same food resources, even though they seem to exploit them in different quantities and frequencies. Future research should focus on the species of Aegla whose diets have not yet been described, and use available data to inform trophic network analyses and models.
Objectives The aim of this work was to investigate the antinociceptive property of α‐phellandrene (α‐PHE) in experimental nociception models and possible mechanisms involved.
Methods Mass ...spectrometry was used to evaluate the purity and molecular mass of α‐PHE. Macrophages from mice peritoneal cavity were used in an MTT test. Rodents were used in tests of chemical and mechanical nociception. In the study of the mechanisms, the animals were treated with pharmacological tools and then submitted to the glutamate test.
Key findings α‐PHE purity was 98.2% and molecular mass 136.1 Da. α‐PHE did not show cytotoxicity. In the writhing and capsaicin tests, α‐PHE promoted the antinociceptive effect in all evaluated doses (minimum dose 3.125 mg/kg). In the formalin test, α‐PHE (50 mg/kg) was effective in inhibiting both phases. In the glutamate test, the monoterpene (12.5 mg/kg) decreased the nociceptive response. In carrageenan‐induced hyperalgesia, α‐PHE (50 mg/kg) decreased the hypernociception index. In the study of the mechanisms involved, pretreatment with naloxone reversed the α‐PHE antinociceptive effect, the same occurred with glibenclamide, l‐arginine, atropine and yohimbine. α‐PHE did not show muscle relaxant activity or central depressant effects in open field and rota rod tests.
Conclusions α‐PHE has an antinociceptive effect and it possibly involves the glutamatergic, opioid, nitrergic, cholinergic and adrenergic systems.
Ionizing radiation has been shown to arrest spermatogenesis despite the presence of surviving stem spermatogonia, by blocking their differentiation. This block is a result of damage to the somatic ...environment and is reversed when gonadotropins and testosterone are suppressed, but the mechanisms are still unknown. We examined spermatogonial differentiation and Sertoli cell factors that regulate spermatogonia after irradiation, during hormone suppression, and after hormone suppression combined with Leydig cell elimination with ethane dimethane sulfonate. These results showed that the numbers and cytoplasmic structure of Sertoli cells are unaffected by irradiation, only a few type A undifferentiated (Aund) spermatogonia and even fewer type A1 spermatogonia remained, and immunohistochemical analysis showed that Sertoli cells still produced KIT ligand (KITLG) and glial cell line-derived neurotrophic factor (GDNF). Some of these cells expressed KIT receptor, demonstrating that the failure of differentiation was not a result of the absence of the KIT system. Hormone suppression resulted in an increase in Aund spermatogonia within 3 days, a gradual increase in KIT-positive spermatogonia, and differentiation mainly to A3 spermatogonia after 2 weeks. KITL (KITLG) protein expression did not change after hormone suppression, indicating that it is not a factor in the stimulation. However, GDNF increased steadily after hormone suppression, which was unexpected since GDNF is supposed to promote stem spermatogonial self-renewal and not differentiation. We conclude that the primary cause of the block in spermatogonial development is not due to Sertoli cell factors such (KITL\GDNF) or the KIT receptor. As elimination of Leydig cells in addition to hormone suppression resulted in differentiation to the A3 stage within 1 week, Leydig cell factors were not necessary for spermatogonial differentiation.
The present study was designed to evaluate whether tissue preparation by glutaraldehyde and glycol methacrylate (G/GMA) improves the diagnostic assessment of testicular biopsies from azoospermic men ...when compared to the standard tissue preparation using Bouin's solution and paraffin. We prospectively included a total of 21 testicular biopsies of sexually mature men aged 29-50 years with infertility and azoospermia. One testicular biopsy fragment from each patient was processed by the G/GMA method, whereas another tissue fragment was contemporarily processed by the conventional Bouin/paraffin (B/P) method. The G/GMA method provided better resolution of cytological details of the seminiferous epithelium, changing the final diagnosis in four cases. The medians of Bergmann's spermatogenesis scores were 0.25 (interquartile range 0.04-0.88) for B/P preparations and 0.79 (interquartile range 0.17-0.96) for G/GMA preparations. Both techniques allowed accurate prediction of sperm recovery from the biopsies (B/P, area under the receiver operating characteristics ROC curve 0.88, 95% confidence interval CI 0.75-1.00; G/GMA, area under the ROC curve 0.94, 95% CI 0.86-1.00). We conclude that human testicular biopsy preparation with G/GMA improved image resolution under light microscopy and produced more reliable results for the evaluation of spermatogenesis in comparison with B/P, allowing a more precise fertility-oriented diagnosis in azoospermic men.
Abbreviations: B/P: Bouin/paraffin; GMA: glycol methacrylate; G/GMA: glutaraldehyde and glycol methacrylate; ICSI: intracytoplasmic sperm injection; OA: obstructive azoospermia; NOA: nonobstructive azoospermia; TESE: testicular sperm extraction.
Great efforts have been made to preserve manatees. Recently, a hybrid zone was described between Trichechus inunguis (TIN) and the Trichechus manatus manatus (TMM) in the Amazon estuary. Cytogenetic ...data on these sirenians are limited, despite being fundamental to understanding the hybridization/introgression dynamics and genomic organization in Trichechus. We analyzed the karyotype of TMM, TIN, and two hybrid specimens (“Poque” and “Vitor”) by classical and molecular cytogenetics. G-band analysis revealed that TMM (2n = 48) and TIN (2n = 56) diverge by at least six Robertsonian translocations and a pericentric inversion. Hybrids had 2n = 50, however, with Autosomal Fundamental Number (FNA) = 88 in “Poque” and FNA = 74 in “Vitor”, and chromosomal distinct pairs in heterozygous; additionally, “Vitor” exhibited heteromorphisms and chromosomes whose pairs could not be determined. The U2 snDNA and Histone H3 multi genes are distributed in small clusters along TIN and TMM chromosomes and have transposable Keno and Helitron elements (TEs) in their sequences. The different karyotypes observed among manatee hybrids may indicate that they represent different generations formed by crossing between fertile hybrids and TIN. On the other hand, it is also possible that all hybrids recorded represent F1 and the observed karyotype differences must result from mechanisms of elimination.
Abstract We evaluated the fish composition and ecological attributes of the ichthyofauna collected in a limnological zone of the Taquaruçu Reservoir, lower Paranapanema River. Information about the ...fish community was updated when compared to the previous study (2006). Non-metric multidimensional scaling (NMDS) showed differences in species composition between periods and community weighted means (CWMs) exhibited changes in functional composition over time. Four functional indices were used in the principal coordinate analysis (PcoA) to measure changes in the functional space of species, whereas functional β-diversity inspected differences in the traits composition between the periods. 1,203 individuals were sampled of 43 species, being 16 non-native and 14 new records. Compared to 2006, 27 species were absent, most of them native to Loricariidae and Anostomidae, while Curimatidae and Pimelodidae decreased in abundance. Functional indexes showed a reduction in functional diversity, whereas new species records exhibited functional redundancy. It might have occurred a simplification of the fish community over time, excluding the migratory and specialists species such as the herbivores and detritivores. Accordingly, we concluded that the ichthyofauna of the Taquaruçu Reservoir might have been undergoing a process towards biotic homogenization.
Resumo Avaliamos a composição de peixes e atributos ecológicos da ictiofauna coletada em uma zona limnológica do reservatório de Taquaruçu, baixo rio Paranapanema. As informações sobre a comunidade de peixes foram atualizadas quando comparadas ao estudo anterior (2006). O escalonamento multidimensional não métrico (NMDS) mostrou diferenças na composição de espécies entre os períodos, e as médias ponderadas da comunidade (CWMs) exibiram mudanças na composição funcional ao longo do tempo. Quatro índices funcionais foram utilizados na análise de coordenadas principais (PcoA) para medir as mudanças no espaço funcional das espécies, enquanto a β-diversidade funcional inspecionou diferenças na composição de traços entre os períodos. Foram amostrados 1,203 indivíduos de 43 espécies, sendo 16 não-nativas e 14 novos registros. Em comparação com 2006, 27 espécies estavam ausentes, a maioria nativa de Loricariidae e Anostomidae, enquanto Curimatidae e Pimelodidae diminuíram em abundância. Os índices funcionais mostraram redução na diversidade funcional, enquanto novos registros de espécies exibiram redundância funcional. Pode ter ocorrido uma simplificação da comunidade de peixes ao longo do tempo, excluindo as espécies migradoras e especialistas como os herbívoros e detritívoros. Dessa forma, concluímos que a ictiofauna do reservatório de Taquaruçu pode estar sofrendo um processo de homogeneização biótica.
The N-salicyloyltryptamine (NST) is an indole derivative compound analogue to the alkaloid N-benzoyltryptamine. In the present study, the antiedematogenic activity of NST was investigated in animal ...models. Firstly, the acute toxicity for NST was assessed according to the OECD Guideline no. 423. The potential NST-induced antiedematogenic activity was evaluated by carrageenan-induced paw edema in rats, as well as by dextran-, compound 48/80-, histamine-, serotonin-, capsaicine-, and prostaglandin E2-induced paw edema in mice. The effect of NST on compound 48/80-induced ex vivo mast cell degranulation on mice mesenteric bed was investigated. No death or alteration of behavioral parameters was observed after administration of NST (2000 mg/kg, i.p.) during the observation time of 14 days. The NST (100 and 200 mg/kg, i.p.) inhibited the carrageenan-induced edema from the 1st to the 5th hour (**p<0.01; ***p<0.001). The edematogenic activity induced by dextran, compound 48/80, histamine, serotonin, capsaicin, and prostaglandin E2 was inhibited by NST (100 mg/kg, i.p.) throughout the observation period (**p<0.01; ***p<0.001). The pretreatment with NST (50, 100 or 200 mg/kg, i.p) attenuates the compound 48/80-induced mast cell degranulation (**p<0.01; ***p<0.001). Thus, the inhibition of both mast cell degranulation and release of endogenous mediators are probably involved in the NST-induced antiedematogenic effect.
In the search of hepatoprotective agents from natural sources, α- and β-amyrin, a triterpene mixture isolated from the trunk wood resin of folk medicinal plant,
Protium heptaphyllum was tested ...against acetaminophen-induced liver injury in mice. Liver injury was analysed by quantifying the serum enzyme activities and by histopathological observations. In mice, acetaminophen (500
mg/kg, p.o.) caused fulminant liver damage characterized by centrilobular necrosis with inflammatory cell infiltration, an increase in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, a decrease in hepatic glutathione (GSH) and 50% mortality. Pretreatment with α- and β-amyrin (50 and 100
mg/kg, i.p. at 48, 24, and 2
h before acetaminophen) attenuated the acetaminophen-induced acute increase in serum ALT and AST activities, replenished the depleted hepatic GSH, and considerably reduced the histopathological alterations in a manner similar to
N-acetylcysteine, a sulfhydryls donor. Also, the acetaminophen-associated mortality was completely suppressed by terpenoid pretreatment. Further, α- and β-amyrin could potentiate the pentobarbital (50
mg/kg, i.p.) sleeping time, suggesting the possible suppression of liver cytochrome-P450. These findings indicate the hepatoprotective potential of α- and β-amyrin against toxic liver injury and suggest that the diminution in oxidative stress and toxic metabolite formation as likely mechanisms involved in its hepatoprotection. In conclusion, this study supports the traditional use of
Protium heptaphyllum resin as a medicinal agent and suggests the feasibility of developing herbal drugs for treatment of liver disorders.
This study investigated the pre- and postnatal effects of protein restriction (8% vs 20% crude protein) on different parameters of spermatogenesis in adult rat offspring. Body and testis weights as ...well as the seminiferous tubular diameter were reduced in those animals that received the protein-restricted diet after weaning, although these parameters recovered when a 20% protein diet was offered subsequently. The numbers of spermatogonia, spermatocytes, spermatids and Leydig cells were reduced in undernourished animals, whilst the Sertoli cell number did not change. Prenatal programming effect was observed only in the spermatogonial or proliferative phase of spermatogenesis. However, the intake of the normal protein diet after weaning brought many of the testicular parameters evaluated back to normal in 70-day-old rats. A significant reduction of the meiotic index, Sertoli cell supporting capacity and spermatogenic efficiency was observed in animals subjected to protein undernutrition throughout their lives. The data presented show that protein restriction impairs the normal development of the testis in different ways, depending on the period during which the restriction was imposed, and the negative effects on spermatogenesis are more severe when undernutrition occurs from conception to adulthood; however, the return to a normal protein diet after weaning recovers the spermatogenic process.
The present work reports the anti-inflammatory and antinociceptive activities of the ethanol extract obtained from the stem bark of Sterculia striata A. St.-Hil. & Naudin (Ss-EtOH) in the ...experimental models of edema induced by carrageenan, dextran, or histamin and nociception induced by chemical stimuli, such as acetic acid, formalin, capsaicin, or glutamate. The Ss-EtOH (50 mg/kg) promoted a marked inhibition on the hind paw edema induced by carrageenan or dextran (30% and 73%, respectively). Besides, Ss-EtOH (25 mg/kg) exhibited a slight activity (30%) on the hind paw edema induced by histamin. The Ss-EtOH (12.5 and 25 mg/kg) showed the antinociceptive activity on chemical stimuli induced by acetic acid (65.59% and 38.37%, respectively), formalin, in the initial (35.08% and 31.5%, respectively) and late phases (44.09% and 83.57%, respectively), capsaicin (43.77% and 51.31%, respectively), or glutamate (36.6% and 52.12%, respectively). Regarding the possible mechanism involved in the antinociceptive effect, Ss-EtOH (12.5 mg/kg) showed a decrease in the antinociceptive effect (65.8%) in the acetic acid model after pretreatment with naloxone. Thus, opioid mechanisms might be underlying this response.
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