Three viruses found in the braconid parasitoid Microplitis croceipes and their implications in biological control programs

Productivity and longevity decreased in a laboratory colony of the parasitoid wasp Microplitis croceipes (Cresson) (Hymenoptera: Braconidae). Using light microscopy, it was determined that the colony was free of microsporidia. However, samples of the colony examined for pathogens by electron microscopy revealed three types of viruses: a nonpathogenic polydnavirus which is produced by all female wasps; a nonoccluded baculovirus which is pathogenic to late-stage pupae and adults; and a picorna-like virus which is present in larvae, pupae, and adults. The nonoccluded baculovirus was eliminated from the laboratory colony of M. croceipes by selection of progeny from wasps which had oviposited within 2 to 3 days after emergence from the cocoons and which had lived for at least 14 days post-emergence. Upon death, the wasps were examined by negative stain electron microscopy and only progeny from baculovirus-free wasps were retained. Parasitoid colonies should be systematically examined for pathogenic viruses that may reduce their productivity and efficacy as biological control agents. In addition, exotic parasitoids and predators should be evaluated for viruses and other pathogens while in quarantine.     

Fixed-time artificial insemination protocols on brazilian locally adapted breed gilts on ovulatory response and embryo production

The aim of this study was to use estrus synchronization protocols to favor fixed-time artificial insemination and consequently fixed-time embryo collection, and increase embryo production using eCG, in gits. In a cross over design, nine Piau breed gilts were subjected to 18 days of oral progesterone; P4 group did not receive any further; GnRH group received 25µg of GnRH 104 hours after the final application of P4; and eCG+GnRH group received 1000IU of eCG 24 hours after the final P4 in addition to GnRH for subsequent embryo collection, that was performed six days after first AI, by laparotomy. Artificial insemination was performed after 12 and 24 hours of estrus in P4 group, and 128 and 144 hours in GnRH and eCG+GnRH groups. The number of CL (8.6±3.9; 8.3±2.1; 26.7±15.0) and anovulatory follicles (4.3±3.7; 3.9±3.9; 17.2±9.5) was higher in the eCG+GnRH gilts (P<0.05). However, the use of 1000 IU of eCG reduced (P<0.05) the number of total structures (5.2±3.6; 5.1±3.1; 1.7±2.7), viable embryos (5.0±3.5; 4.8±3.3; 0.4±0.7), freezable embryos (3.6±3.4; 3.3±3.8; 0.1±0.3) and recovery rate (63.7±38.9; 58.6±24.7; 5.38±9.5). P4 and GnRH protocols were effective in the production and recovery of embryos. However, the use of 1000 IU of eCG, 24 hours after P4, was not effective in promoting the production of embryos, although the animals had superovulated.     

What drives interspecies graft union success? Exploring the role of phylogenetic relatedness and stem anatomy

The underlying mechanisms that determine whether two species can form a successful graft union (graft compatibility) remain obscure. Two prominent hypotheses are (1) the more closely related species are, the higher the graft success and (2) the vascular anatomy at the graft junction influences graft success. In this paper these two hypotheses are examined in a systematic way using graft combinations selected from a range of (a) phylogenetically close and more distant legume species, (b) species displaying different germination patterns and (c) scions and rootstocks possessing contrasting stem tissues and vascular patterns. Relatedness of species was not a good predictor of graft compatibility, as vascular reconnection can occur between distantly related species and can fail to occur in some more closely related species. Similarly, neither the stem tissues present at the graft junction nor the vascular anatomy correlated with the success of vascular reconnection. Relatedness and stem anatomy therefore do not appear to be the determining factors in successful vascular reconnection after grafting in legumes. These results are discussed in conjunction with other hypotheses such as the role of auxin.     

Onychomycosis Due to Neoscytalidium Treated with Oral Terbinafine, Ciclopirox Nail Lacquer and Nail Abrasion: A Pilot Study of 25 Patients

Background

Onychomycosis by Neoscytalidium constitutes chronic infection of the nails, and its frequency has increased in recent decades. Currently, no effective standard treatment exists and literature data remain scarce. This work aimed to conduct a pilot project of combined treatment for this infection.

Methods

Thirty patients were divided into three treatment groups: oral terbinafine plus ciclopirox nail lacquer twice a week; ciclopirox nail lacquer twice a week; and ciclopirox nail lacquer 5 days a week, all associated with nail abrasion when required, for 12 months, with 6 months posttreatment follow-up. Clinical and mycological criteria were used for evaluation.

Results

Twenty-five patients completed the study. Significant clinical lesion reduction in disease occurred in all three treatment groups: 21 patients (84 %) entered the study with more than 50 % of diseased nail plate, at the end of treatment, and at 6-month follow-up, 84 and 96 %, respectively, presented less than 25 % nail lesion. Negative microscopy was observed in 36 % of the patients at the end of treatment and in 24 % of the patients at 6-month follow-up. At treatment completion (12 months), culture was negative in 21 patients (84 %) and in 18 (72 %) at follow-up. It was not possible to establish any clinical or mycological statistical differences between groups (p > 0.05). Global medical evaluation upon treatment completion revealed that one patient (4 %) presented complete cure, 8 (32 %) presented partial cure, 16 (64 %) presented therapeutic failure. At the end of follow-up period, 6 patients (24 %) were considered to have recurrence/reinfection.

Conclusions

The results obtained at the 6-month period of follow-up showed marked improvement (96 % of clinical improvement and 72 % of negative culture) of the patients treated for onychomycosis caused by Neoscytalidium in the three tested groups with no statistical differences between them. Multicentric studies with greater number of patients enrolled are necessary to confirm these results.     

Characterisation of the effects of leaf galls of Clusiamyia nitida (Cecidomyiidae) on Clusia lanceolata Cambess. (Clusiaceae): Anatomical aspects and chemical analysis of essential oil

Galls develop in different plant organs and are induced by the activity of various organisms. Some studies have investigated the ecological interactions between species of Clusia and gall-inducing insects. The goal of our study is to characterise changes in leaf anatomy caused by the activity of gall insects in Clusia lanceolata. Additionally, we also investigated the chemical composition of volatile compounds of normal leaves and those with galls to detect possible effects on the host plants. For anatomical studies, we used botanical material fixed in FAA₅₀. Transversal sections of the leaf blade were obtained from samples of leaves located on the third and fourth nodes from both male and female individuals. Material was studied from both sexes both with unaffected leaves and leaves containing galls. Fresh leaves of C. lanceolata were used for the extraction of volatile compounds, which were submitted to stem distillation using a modified Clevenger apparatus determining the oil yields subsequently (w/w). The unaffected leaves of female and male individuals of C. lanceolata exhibit similar anatomical structures. However, galls on leaves of both sexes show anatomical differences. The activity of the gall insect Clusiamyia nitida induces several changes in the foliar anatomy and the distribution of metabolic compounds in new tissues during gall development. However, the larvae are not able to induce significant changes in the volatile compounds of inflected leaves from male and female individuals.     

Mechanisms of outer membrane vesicle entry into host cells

Bacterial outer membrane vesicles (OMVs) are nano‐sized compartments consisting of a lipid bilayer that encapsulates periplasm‐derived, luminal content. OMVs, which pinch off of Gram‐negative bacteria, are now recognized as a generalized secretion pathway which provides a means to transfer cargo to other bacterial cells as well as eukaryotic cells. Compared with other secretion systems, OMVs can transfer a chemically extremely diverse range of cargo, including small molecules, nucleic acids, proteins, and lipids to proximal cells. Although it is well recognized that OMVs can enter and release cargo inside host cells during infection, the mechanisms of host association and uptake are not well understood. This review highlights existing studies focusing on OMV‐host cell interactions and entry mechanisms, and how these entry routes affect cargo processing within the host. It further compares the wide range of methods currently used to dissect uptake mechanisms, and discusses potential sources of discrepancy regarding the mechanism of OMV uptake across different studies.     

Tumor-Stroma Mechanics Coordinate Amino Acid Availability to Sustain Tumor Growth and Malignancy

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Elevated Prolactin during Pregnancy Drives a Phenotypic Switch in Mouse Hypothalamic Dopaminergic Neurons

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Explant type and natural ventilation systems influence growth and content of carvacrol and thymol of Lippia gracilis Schauer

The objective of this study was to evaluate the effects of different natural ventilation systems and explant types on the growth and volatile compound content of Lippia gracilis cultured in vitro. The treatments consisted of four membrane systems (without membrane, with one, two, and four porous membranes) and two explant types (nodal segments with and without a pair of leaves). The evaluation of growth, photosynthetic pigments and chemical analysis of the volatile fraction were performed at 35 days of cultivation in half strength MS basal medium. Natural ventilation systems significantly influenced the in vitro growth and volatile fraction of L. gracilis. Explants with a pair of leaves obtained the best experimental responses. The natural ventilation system with four membranes provided the best growth parameters and leaf area response of L. gracilis explants with leaves. The photosynthetic pigments decreased with an increase in the number of porous membranes in the culture flask. Variations in the number, content, and profile of volatile compounds under the influence of natural ventilation systems were observed. Major constituents such as ρ-cymene, γ-terpinene, thymol, carvacrol, and E-caryophyllene, regardless of experimental conditions, were identified. The highest carvacrol and thymol contents were observed in plantlets grown in culture flasks with four porous membranes. To maximize the content of carvacrol and thymol from the in vitro culture of L. gracilis, explants with a pair of leaves and four porous membranes in culture flasks are recommended for use.