Scanning Electron Microscopic Aids For Identification Of Larval And Post-Larval Bivalves

The identification of bivalve larvae and early postlarvae in plankton and benthic samples has long been a challenge, hampering both basic and applied research efforts in marine, estuarine, and freshwater environments. The usefulness of published optical micrographs of the early life-history stages of bivalves is limited because of the great morphological similarity of the imaged articulated shells, particularly at the early (straight-hinge) developmental stages. While a number of techniques have been refined in recent years and show promise for use in routine identifications of larval and post-larval bivalves (e.g., single-step nested multiplex polymerase chain reaction; in situ hybridization protocols through color coding with taxon-specific, dye-labeled DNA probes; coupled fluorescence in situ hybridization and cell sorting; and image analysis techniques using species-specific shell birefringence patterns under polarized light), no adequate comprehensive reference source exists that accurately depicts the morphology and morphometry of the shells of larval and post-larval stages of target bivalve species in a consistent format to assist in identification of such stages. To this end, scanning electron micrograph (SEM) sequences are presented of the disarticulated shell valves of laboratory-reared larval and post-larval stages of 56 species of bivalve molluscs from a wide spectrum of marine, estuarine, and freshwater habitats. Emphasis is placed on the usefulness of the morphology and morphometrics of consistently-oriented, disarticulated shell valves and associated hinge structures in discriminating the early life-history stages of these various bivalve species. Although the scanning electron micrograph sequences presented accurately depict the gross morphologies/morphometrics and hinge structures of the disarticulated shell valves of the larvae and/or postlarvae of the 56 species of bivalves, it is important to emphasize that a scanning electron microscope is not necessary to observe even fine hinge structures associated with the early ontogenetic stages of these species. Such structures are readily visible using a wide range of optical compound microscopes equipped with high-intensity reflected light sources, although the disarticulated shell valves must be viewed in several planes of focus to discern the often subtle details seen clearly in the scanning electron micrographs. These morphological characters provide researchers with invaluable aids for the routine identification of the early life-history stages of these species isolated from plankton and benthic samples

Actions of Camptothecin Derivatives on Larvae and Adults of the Arboviral Vector Aedes aegypti

Mosquito-borne viruses including dengue, Zika, and Chikungunya viruses, and parasites such as malaria and Onchocerca volvulus endanger health and economic security around the globe, and emerging mosquito-borne pathogens have pandemic potential. However, the rapid spread of insecticide resistance threatens our ability to control mosquito vectors. Larvae of Aedes aegypti were screened with the Medicines for Malaria Venture Pandemic Response Box, an open-source compound library, using INVAPP, an invertebrate automated phenotyping platform suited to high-throughput chemical screening of larval motility. We identified rubitecan (a synthetic derivative of camptothecin) as a hit compound that reduced A. aegypti larval motility. Both rubitecan and camptothecin displayed concentration dependent reduction in larval motility with estimated EC_{50} of 25.5 ± 5.0 µM and 22.3 ± 5.4 µM, respectively. We extended our investigation to adult mosquitoes and found that camptothecin increased lethality when delivered in a blood meal to A. aegypti adults at 100 µM and 10 µM, and completely blocked egg laying when fed at 100 µM. Camptothecin and its derivatives are inhibitors of topoisomerase I, have known activity against several agricultural pests, and are also approved for the treatment of several cancers. Crucially, they can inhibit Zika virus replication in human cells, so there is potential for dual targeting of both the vector and an important arbovirus that it carries

Harvey Cushing: early use of tendon transfers for repair of foot deformity: A historical case report

We describe 4 cases of tendon transfers for correction of foot deformities, which were performed by Harvey Cushing in 1898

Suicide ideation of individuals in online social networks

Suicide explains the largest number of death tolls among Japanese adolescents in their twenties and thirties. Suicide is also a major cause of death for adolescents in many other countries. Although social isolation has been implicated to influence the tendency to suicidal behavior, the impact of social isolation on suicide in the context of explicit social networks of individuals is scarcely explored. To address this question, we examined a large data set obtained from a social networking service dominant in Japan. The social network is composed of a set of friendship ties between pairs of users created by mutual endorsement. We carried out the logistic regression to identify users' characteristics, both related and unrelated to social networks, which contribute to suicide ideation. We defined suicide ideation of a user as the membership to at least one active user-defined community related to suicide. We found that the number of communities to which a user belongs to, the intransitivity (i.e., paucity of triangles including the user), and the fraction of suicidal neighbors in the social network, contributed the most to suicide ideation in this order. Other characteristics including the age and gender contributed little to suicide ideation. We also found qualitatively the same results for depressive symptoms.Comment: 4 figures, 9 table

Hallux valgus angle as main predictor for correction of hallux valgus

Contains fulltext : 70112.pdf ( ) (Open Access)BACKGROUND: It is recognized that different types of hallux valgus exist. Classification occurs with radiographic and clinical parameters. Severity of different parameters is used in algorithms to choose between different surgical procedures. Because there is no consensus about each parameter nor their cut-off point we conducted this study to analyze the influence of these variables on the postoperative hallux valgus angle. METHODS: After informed consent 115 patients (136 feet) were included. Bunionectomy, osteotomy, lateralization of the distal fragment, lateral release and medial capsulorrhaphy were performed in all patients. Data were collected on preoperative and postoperative HVA, IMA and DMAA measurements. Forty cases were included since our findings in a previous article 1, therefore, current data concern an expanded study group with longer follow-up and were not published before. At least two-year follow-up data were evaluated with logistic regression and independent t-tests. RESULTS: Preoperative HVA was significant for prediction of postoperative HVA in logistic regression. IMA and DMAA were not significant for prediction of postoperative HVA in logistic regression, although they were significantly increased in larger deformities. In patients with preoperative HVA of 37 degrees or more, satisfactory correction could be obtained in 65 percent. The other nine of these 26 patients developed subluxation. CONCLUSION: The preoperative HVA was the main radiological predictor for correction of hallux valgus, correction rate declined from preoperative HVA of 37. IMA and DMAA did have a minor role in patients with preoperative HVA lower than 37 degrees, however, likely contributed to preoperative HVA of 37 degrees or more

Rapid cryopreservation of five mammalian and one mosquito cell line at -80°C while attached to flasks in a serum free cryopreservative

Cell culturing, and the requisite storage of cell lines at ultra-low temperatures, is used in most laboratories studying or using eukaryotic proteomics, genomics, microarray, and RNA technologies. In this study we have observed that A72(dog), CRFK(cat), NB324K(human), MCF7(human), WI38(human), and C636(mosquito) cells were effectively cryopreserved at -80°C while attached to the substratum of 25cm(2 )tissue culture flasks. This was accomplished using a serum free crypreservative recently developed by Corsini and co-workers. The technique allows for significant savings of time and money in laboratories that rapidly process numerous cell lines

A methodology for parameter estimation in seaweed productivity modelling

This paper presents a combined approach for parameter estimation in models of primary production. The focus is on gross primary production and nutrient assimilation by seaweeds. A database of productivity determinations, biomass and mortality measurements and nutrient uptake rates obtained over one year for Gelidium sesquipedale in the Atlantic Ocean off Portugal has been used. Annual productivity was estimated by harvesting methods, and empirical relationships using mortality/ wave energy and respiration rates have been derived to correct for losses and to convert the estimates to gross production. In situ determinations of productivity have been combined with data on the light climate (radiation periods, intensity, mean turbidity) to give daily and annual productivity estimates. The theoretical nutrient uptake calculated using a 'Redfield ratio' approach and determinations of in situ N and P consumption by the algae during incubation periods have also been compared. The results of the biomass difference and incubation approaches are discussed in order to assess the utility of coefficients determined in situ for parameter estimation in seaweed production models

Four decades of conjoined twins at Red Cross Children's Hospital - lessons learned

No Abstract. South African Medical Journal Vol. 96(9) (Part 2) 2006: 931-94