Biological Data on Anovia punica Gordon (Coleoptera: Coccinellidae), a Predator of Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae)

The coccinellid beetle Anovia punica Gordon (Coleoptera: Coccinellidae: Noviini) is an important predator of the Colombian fluted scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae). In order to gather information on the biological traits of A. punica, we conducted a series of studies, including of the developmental time of each life history stage, estimation of life table parameters, and predation rates under laboratory conditions [25.1 ± 1.6°C, with 70.5 ± 7.3% RH, and natural light regime, approx. 12:12 (L:D) h]. Developmental stages of A. punica were categorized as follows: egg stage, four larval instars, prepupal instar, pupal instar, and adult. Developmental time from egg to adult emergence averaged 29.41 ± 1.85 days, and 47.6% of the eggs developed to adulthood. Female and male survival was 94.42 and 90 days, respectively. Life table parameters show that one female of A. punica is replaced by 86 females (R ₀), the intrinsic growth rate (r _m ) was 0.1115, the average generation time (T) was 40 days, and the doubling time (D _t ) was 6.2 days. The life table parameters suggest that A. punica can be used as a potential predator of C. multicicatrices and, more importantly, provided baseline information for a mass-rearing protocol. This is the first detailed study on the biology of A. punica that reports the potential of this predator as a biological control agent for scale insects of the tribe Iceryini.

On the Biology of the Colombian Fluted Scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae)

The Colombian fluted scale Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae) is a polyphagous insect pest native to continental Colombia and reported on 148 species, mainly palms (Arecaceae); mango, Mangifera indica (Anacardiaceae); and leguminous trees and shrubs (Fabaceae). The biology and ecological parameters of C. multicicatrices were investigated using as a host plant Caesalpinia pluviosa var. peltophoroides (Fabaceae) under two environmental conditions: semifield (max temp., 31.5 ± 3.0°C; max. RH, 78.9 ± 6.0%) and a glass house (max. temp., 37.1 ± 5.1°C, max. RH, 67.0 ± 6.2%) in the premises of Corpoica, Palmira Research Station. The duration of the different developmental stages was highly different under both temperature conditions. First- and third-instar nymphs, the period of ovisac growth of the adult, and the duration of the life cycle were significantly higher in the semifield conditions compared to the glass house conditions. In contrast, the second-instar nymph stage was shorter in the semifield conditions. The duration of the fourth-instar stage (adult) and the reproductive period were the same in both environments. As for the evaluated ecological parameters, a great difference was found between the two environmental conditions, where the net reproductive rate (R _o) and mean generation time (T) were significantly higher in the semifield conditions than in the glass house conditions. The obtained biological and ecological information is an essential tool for finding strategies to control this insect pest. This is the first detailed study on the biology of a species in the genus Crypticerya Cockerell.

Development and Reproduction of Brethesiella cf. abnormicornis (Girault) (Hymenoptera: Encyrtidae), a Parasitoid of the Colombian Fluted Scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae)

Studies on the development and reproduction of Brethesiella cf. abnormicornis (Girault) (Hymenoptera: Encyrtidae), a parasitoid of the Colombian fluted scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae), were conducted under laboratory conditions. The duration of the life cycle, adult longevity, fecundity, and population parameters were determined. The parasitoid takes about 29 d to complete a single generation (from egg to adult). In addition, population parameters show that one female wasp is replaced by nearly 32 females, with a female-to-male sex ratio of 2:1. Population parameters estimated in this study can be considered baseline information for a mass-rearing protocol. This is the first detailed study of the biology of a species of Brethesiella, where the duration of all larval stages of the parasitoid is determined, being an important contribution for further biological studies of endoparasitoids.

Metacarpophalangeal and interphalangeal joint arthrodesis: a comparative study between tension band and compression screw fixation

A retrospective, comparative cohort study was performed of metacarpophalangeal or proximal interphalangeal joint arthrodesis with either tension band (n = 28) or compression (Acutrak Mini) screw (n = 29) methods. We compared rate of union, healing time, complications, and re-operation rate. Union was achieved in 26/28 (92.8%) of the tension band group (9.4 weeks) and 24/28 (85.7%) of the compression screw group (9.8 weeks). Only 28 patients in the screw group were assessed for union as one patient in the screw group sustained a fracture at the time of insertion and was converted to tension band fixation. The complication rate was 8/28 (28.6%) in the tension band group and 8/29 (27.6%) in the compression screw group. Re-operation rate was 9/28 (32.1%) in the tension band group and 1/29 (3.6%) in the compression screw group. Our findings indicate that bone healing, healing time, and complications are similar in both groups. The tension band technique had a significantly higher re-operation rate (hardware removal), but was the technique for salvage following failure of the screw technique.

Sorting nexin 17 regulates ApoER2 recycling and reelin signaling

ApoER2 is a member of the low density-lipoprotein receptor (LDL-R) family. As a receptor for reelin, ApoER2 participates in neuronal migration during development as well as synaptic plasticity and survival in the adult brain. A previous yeast two-hybrid screen showed that ApoER2 is a binding partner of sorting nexin 17 (SNX17) - a cytosolic adaptor protein that regulates the trafficking of several membrane proteins in the endosomal pathway, including LRP1, P-selectin and integrins. However, no further studies have been performed to investigate the role of SNX17 in ApoER2 trafficking and function. In this study, we present evidence based on GST pull-down and inmunoprecipitation assays that the cytoplasmic NPxY endocytosis motif of ApoER2 interacts with the FERM domain of SNX17. SNX17 stimulates ApoER2 recycling in different cell lines including neurons without affecting its endocytic rate and also facilitates the transport of ApoER2 from the early endosomes to the recycling endosomes. The reduction of SNX17 was associated with accumulation of an ApoER2 carboxy-terminal fragment (CTF). In addition, in SNX17 knockdown cells, constitutive ApoER2 degradation was not modified, whereas reelin-induced ApoER2 degradation was increased, implying that SNX17 is a regulator of the receptor's half-life. Finally, in SNX17 silenced hippocampal and cortical neurons, we underscored a positive role of this endosomal protein in the development of the dendritic tree and reelin signaling. Overall, these results establish the role of SNX17 in ApoER2 trafficking and function and aid in identifying new links between endocytic trafficking and receptor signaling.

A sorting nexin 17-binding domain within the LRP1 cytoplasmic tail mediates receptor recycling through the basolateral sorting endosome

Sorting nexin 17 (SNX17) is an adaptor protein present in early endosomal antigen 1 (EEA1)-positive sorting endosomes that promotes the efficient recycling of low-density lipoprotein receptor-related protein 1 (LRP1) to the plasma membrane through recognition of the first NPxY motif in the cytoplasmic tail of this receptor. The interaction of LRP1 with SNX17 also regulates the basolateral recycling of the receptor from the basolateral sorting endosome (BSE). In contrast, megalin, which is apically distributed in polarized epithelial cells and localizes poorly to EEA1-positive sorting endosomes, does not interact with SNX17, despite containing three NPxY motifs, indicating that this motif is not sufficient for receptor recognition by SNX17. Here, we identified a cluster of 32 amino acids within the cytoplasmic domain of LRP1 that is both necessary and sufficient for SNX17 binding. To delineate the function of this SNX17-binding domain, we generated chimeric proteins in which the SNX17-binding domain was inserted into the cytoplasmic tail of megalin. This insertion mediated the binding of megalin to SNX17 and modified the cell surface expression and recycling of megalin in non-polarized cells. However, the polarized localization of chimeric megalin was not modified in polarized Madin-Darby canine kidney cells. These results provide evidence regarding the molecular and cellular mechanisms underlying the specificity of SNX17-binding receptors and the restricted function of SNX17 in the BSE.

An efficient method for variable region assembly in the construction of scFv phage display libraries using independent strand amplification

Phage display library technology is a common method to produce human antibodies. In this technique, the immunoglobulin variable regions are displayed in a bacteriophage in a way that each filamentous virus displays the product of a single antibody gene on its surface. From the collection of different phages, it is possible to isolate the virus that recognizes specific targets. The most common form in which to display antibody variable regions in the phage is the single chain variable fragment format (scFv), which requires assembly of the heavy and light immunoglobulin variable regions in a single gene. In this work, we describe a simple and efficient method for the assembly of immunoglobulin heavy and light chain variable regions in a scFv format. This procedure involves a two-step reaction: (1) DNA amplification to produce the single strand form of the heavy or light chain gene required for the fusion; and (2) mixture of both single strand products followed by an assembly reaction to construct a complete scFv gene. Using this method, we produced 6-fold more scFv encoding DNA than the commonly used splicing by overlap extension PCR (SOE-PCR) approach. The scFv gene produced by this method also proved to be efficient in generating a diverse scFv phage display library. From this scFv library, we obtained phages that bound several non-related antigens, including recombinant proteins and rotavirus particles.