Neural correlates of settlement in veliger larvae of the gastropod,Crepidula fornicata

Settlement behavior of molluscan veliger larvae prior to metamorphosis requires cessation of swimming, accomplished by arrest of prototrochal cilia on the margin of the velum (the larval swimming organ). Ciliary arrest in larvae of gastropods is mediated by an action potential that occurs synchronously across the velum as a consequence of electrical coupling between the prototrochal ciliated cells. We developed a preparation for extracellular recording of such ciliary arrest spikes from intact swimming and crawling veliger larvae of the caenogastropod Crepidula fornicata, using a fine wire electrode. Ciliary arrest spike rates during bouts of substrate crawling were significantly higher than those recorded during preceding swimming periods in larvae that were competent for metamorphosis, but not in precompetent larvae. Spike rates were similar on clean polystyrene substrates, and on substrates that had been coated with a natural cue for metamorphosis (mucus from conspecific adults). We used immunohistochemical methods to localize neuromodulators that might regulate the function of velar cilia. Labeled terminals for serotonin, FMRFamide, and tyrosine hydroxylase (an enzyme for catecholamine synthesis) were located in positions consistent with modulatory effects on the prototrochal ciliated cells. Prototrochal ciliary arrest spike rates and beat frequencies were measured in isolated velar lobes from competent larvae, which were exposed to serotonin, FMRFamide, and dopamine (10^?5 mol L^?1). Serotonin abolished arrest spiking and increased beat frequency; dopamine also increased beat frequency, and FMRFamide depressed it. Competent larvae tested in a small static water column swam to the top of the column when exposed to serotonin, but occupied lower positions than controls when in the presence of dopamine and FMRFamide. The larval nervous system appears to regulate velar functions that are critical for settlement behavior, and is likely to do so by integrating different sensory modalities in an age‐dependent manner.     

Bio-hydrolysis of used soybean oil: environmental-friendly technology using microbial consortium

Biodegradation - In this work, strains of Bacillus subtilis were inoculated in consortium with Rhodotorula mucilaginosa into spent soy oil as aiming to biological treatment and low-cost reuse. The...     

Cross-reactivity and immunotherapeutic potential of BamA recombinant protein from Acinetobacter baumannii

Acinetobacter baumannii is an important nosocomial pathogen. BamA is a protein that belongs to a complex responsible for organizing the proteins on the bacterial outer membrane. In this work, we aimed to evaluate murine immune responses to BamA recombinant protein (rAbBamA) from A. baumannii in an animal model of infection, and to assess cross-reactivity of this target for the development of anti-A. baumannii vaccines or diagnostics. Immunization of mice with rAbBamA elicited high antibody titers and antibody recognition of native A. baumannii BamA. Immunofluorescence also detected binding to the bacterial surface. After challenge, immunized mice demonstrated a 40% survival increase and better bacterial clearance in kidneys. Immunoblot of anti-rAbBamA against other medically relevant bacteria showed binding to proteins of approximately 35 kDa in Klebsiella pneumoniae and Escherichia coli lysates, primarily identified as OmpA and OmpC, respectively. Altogether, our data show that anti-rAbBamA antibodies provide a protective response against A. baumannii infection in mice. However, the response elicited by immunization with rAbBamA is not completely specific to A. baumannii. Although a broad-spectrum vaccine that protects against various pathogens is an appealing strategy, antibody reactivity against the human microbiota is undesired. In fact, immunization with rAbBamA produced noticeable effects on the gut microbiota. However, the changes elicited were small and non-specific, given that no significant changes in the abundance of Proteobacteria were observed. Overall, rAbBamA is a promising target, but specificity must be considered in the development of immunological tools against A. baumannii.     

Paracoccidioidomycosis due to Paracoccidioides brasiliensis S1 associated with acquired immunodeficiency syndrome: A case report

BackgroundParacoccidioidomycosis (PCM) is an endemic disease in Latin America. In immunocompetent hosts, PCM occurs in two main clinical forms: acute and chronic. However, in HIV-infected patients PCM may show up simultaneous manifestations of acute and chronic forms.Case reportWe present the case of a patient diagnosed with HIV who had disseminated skin lesions and generalized lymphadenopathy, as well as respiratory and central nervous system involvement. The PCM diagnosis was confirmed by direct KOH examination, double immunodiffusion and the isolation of the fungus in samples of an abscess in the subcostal region. The isolate was identified as Paracoccidioides brasiliensis S1 by species-specific PCR using primers for protein-coding gene GP43 (exon 2) followed by PCR-RFLP of the alpha-tubulin gene.ConclusionsThere are few data in literature reporting species-specific molecular identification of Paracoccidioides in HIV/PCM patients. Therefore, this case report may contribute to improve the knowledge about this severe disease, its causative cryptic species, and its consequences to patients.     

The intermediate dispersal hypothesis: seed dispersal is maximized in areas with intermediate usage by hoarders

Seed dispersal and predation are paramount for tropical plant diversity. When encountered by scatter-hoarding frugivores, seeds can be either eaten, dispersed or ignored. But even after dispersal, seed caches are still subjected to predation. Many factors are known to influence these dynamics; however, how frequently hoarders use certain patches has seldom been related to cache predation rates. We used the interaction between agoutis (Dasyprocta leporina), a scatter-hoarding rodent, and Joannesia princeps, a tropical tree, as a model to investigate how the number of visits by hoarders in certain areas influences cache predation and seed fate. Camera-traps were used for 30 days in twenty different locations in Tijuca National Park to assess number of visits by agoutis. Thereafter, we placed seed piles on the same areas and determined their fate using the spool-and-line method to track seeds for over one hundred days. We found a non-linear relationship between how often an area is used by hoarders and the final proportion of dispersed seeds. At areas with a low number of visits, proportion of dispersed seeds was low due to low removal. As frequency of visits by hoarders increased, seed removal and the number of dispersal events increased but so did cache predation. Thus, in areas intensively used by hoarders, high cache predation resulted in a low number of dispersed seeds that remained alive in caches. As a result, dispersal was maximized in areas with intermediate use by scatter-hoarders, where there was a balance between primary seed dispersal and cache predation.

     

Diapause initiation and alterations in the life cycle of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) as induced by photoperiodic conditions

Grapholita molesta (Busck) is one of the major pests of Rosaceae, causing significant damage to buds and fruits. In Southern Brazil, its population density is reduced during Rosaceae dormancy months. The present study evaluated the influence of different photoperiods (L:D) (10:14, 11:13, 12:12, 13:11, 14:10 and 16:8) at 25 ± 1oC and 60 ± 10% RH on diapause induction of G. molesta eggs, larvae, prepupae, and pupae. The effects of the photoperiod on the life cycle of non-diapausing insects and on the second generation were also assessed. Prepupal diapause was observed only when eggs and neonates (≤ 12h-old larvae) were exposed to photophases from 10h to 14h long. Development of non-diapausing individuals and those from the second generation tended to be longer in photophases between 10h and 14h long.     

Induction of eosinophil apoptosis by the cyclin-dependent kinase inhibitor AT7519 promotes the resolution of eosinophil-dominant allergic inflammation

Background

Eosinophils not only defend the body against parasitic infection but are also involved in pathological inflammatory allergic diseases such as asthma, allergic rhinitis and contact dermatitis. Clearance of apoptotic eosinophils by macrophages is a key process responsible for driving the resolution of eosinophilic inflammation and can be defective in allergic diseases. However, enhanced resolution of eosinophilic inflammation by deliberate induction of eosinophil apoptosis using pharmacological agents has not been previously demonstrated. Here we investigated the effect of a novel cyclin-dependent kinase inhibitor drug, AT7519, on human and mouse eosinophil apoptosis and examined whether it could enhance the resolution of a murine model of eosinophil-dominant inflammation in vivo.

Methodology/Principal Findings

Eosinophils from blood of healthy donors were treated with AT7519 and apoptosis assessed morphologically and by flow-cytometric detection of annexin-V/propidium iodide staining. AT7519 induced eosinophil apoptosis in a concentration dependent manner. Therapeutic administration of AT7519 in eosinophil-dominant allergic inflammation was investigated using an established ovalbumin-sensitised mouse model of allergic pleurisy. Following ovalbumin challenge AT7519 was administered systemically at the peak of pleural inflammation and inflammatory cell infiltrate, apoptosis and evidence of macrophage phagocytosis of apoptotic eosinophils assessed at appropriate time points. Administration of AT7519 dramatically enhanced the resolution of allergic pleurisy via direct induction of eosinophil apoptosis without detriment to macrophage clearance of these cells. This enhanced resolution of inflammation was shown to be caspase-dependent as the effects of AT7519 were reduced by treatment with a broad spectrum caspase inhibitor (z-vad-fmk).

Conclusions

Our data show that AT7519 induces human eosinophil apoptosis and enhances the resolution of a murine model of allergic pleurisy by inducing caspase-dependent eosinophil apoptosis and enhancing macrophage ingestion of apoptotic eosinophils. These findings demonstrate the utility of cyclin-dependent kinase inhibitors such as AT7519 as potential therapeutic agents for the treatment of eosinophil dominant allergic disorders.     

Factors associated with colposcopy-histopathology confirmed cervical intraepithelial neoplasia among HIV-infected women from Rio De Janeiro, Brazil

Introduction

Despite the availability of preventive strategies (screening tests and vaccines), cervical cancer continues to impose a significant health burden in low- and medium-resourced countries. HIV-infected women are at increased risk for infection with human papillomavirus (HPV) and thus development of cervical squamous intraepithelial neoplasia (CIN).

Methods

Study participants included HIV-infected women enrolling the prospective open cohort of Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation (IPEC/FIOCRUZ). At cohort entry, women were subjected to conventional Papanicolaou test, HPV-DNA test and colposcopy; lesions suspicious for CIN were biopsied. Histopathology report was based on directed biopsy or on specimens obtained by excision of the transformation zone or cervical conization. Poisson regression modeling was used to assess factors associated with CIN2+ diagnosis.

Results

The median age of the 366 HIV-infected women included in the study was 34 years (interquartile range: 28–41 years). The prevalence of CIN1, CIN2 and CIN3 were 20.0%, 3.5%, and 2.2%, respectively. One woman was found to have cervical cancer. The prevalence of CIN2+ was 6.0%. Factors associated with CIN2+ diagnosis in the multivariate model were age < years compared to ≥35 years (aPR  =  3.22 95%CI 1.23–8.39), current tobacco use (aPR  =  3.69 95%CI 1.54–8.78), nadir CD4 T-cell count <350 cells/mm3 when compared to ≥ 350 cells/mm3 (aPR  =  6.03 95%CI 1.50–24.3) and concomitant diagnosis of vulvar and/or vaginal intraepithelial lesion (aPR  =  2.68 95%CI 0.99–7.24).

Discussion

Increased survival through wide-spread use of highly active antiretroviral therapy might allow for the development of cervical cancer. In Brazil, limited cytology screening and gynecological care adds further complexity to the HIV-HPV co-infection problem. Integrated HIV care and cervical cancer prevention programs are needed for the prevention of cervical cancer mortality in this group of women.     

Adjustment of juvenile tuatara to a cooler,southern climate: operative temperatures,emergence behaviour and growth rate

Translocations for conservation often involve species limited to relict distributions. However, uncertainty can exist regarding the ability of source individuals to acclimatise following a shift to a distant location. We investigated the ability of captive-reared juvenile tuatara (Sphenodon punctatus) of Cook Strait stock (41°S) to adjust to outdoor, predator-protected pens within Orokonui Ecosanctuary (45 °S). We examined potential basking and within burrow temperatures, the influence of temperature on emergence, and growth rates in comparison with other locations. Tuatara at Orokonui reached their preferred temperature when basking over summer, and burrows provided protection from freezing over winter. Emergence was temperature-dependent and essentially ceased during winter. Growth rates of Orokonui-held juveniles were within the range for four other captive-rearing facilities and faster than for wild juveniles from a Cook Strait population. As all Orokonui-held juveniles have survived and grown we conclude that the climate at this southern location is suitable to consider a free-release.