Total skin electron irradiation treatment for mycosis fungoides with a new alternate daily treatment schedule to minimize radiation-associated toxicity: a preliminary experience

Conventional total skin electron irradiation (TSEI) for mycosis fungoides (MF) causes radiation toxicity, requiring treatment interruptions that prolong the treatment period, making patient compliance poor. We evaluated an alternate daily treatment schedule of TSEI, using a high dose rate (HDR) to minimize radiation toxicity and shorten the treatment duration. Four patients (aged 45–73 years with MF duration of 7–22 months) were treated by TSEI using HDR. The treatment was given on 5 days/week for 2 weeks followed by treatment on alternate days to deliver a total dose of 36 Gy. All the patients completed treatment in 10 weeks and had complete remission. Radiation toxicity was much less common with this schedule, requiring no treatment interruption. All the patients were until in remission after 60–84 months of follow-up. This schedule of TSEI treatment caused minimal radiation toxicity and allowed completion of treatment over a shorter period, giving good clinical remission and prolonged disease-free survival.     

Further evaluation of higher potency vaccines for early protection of cattle against FMDV direct contact challenge

The effect of administering higher payload FMD vaccines 10 days prior to severe direct contact challenge on protection from clinical disease and sub-clinical infection was investigated in cattle using two antigen payloads (single strength and 10-fold). Regardless of antigen payload, vaccination was shown to significantly reduce the number of clinically infected animals, and significantly reduce virus excretion shortly after challenge, when compared with the unvaccinated group (P<0.05). Although FMDV transmission occurred from single strength vaccinated infected cattle to similarly vaccinated cattle held in indirect contact, no disease was induced in these animals. These studies further confirm that emergency vaccination does significantly reduce clinical disease and sub-clinical virus replication and excretion, particularly early post exposure, thereby reducing the possibility of transmission between animals and herds. To be most effective, however, the results also substantiate that time of vaccination prior to challenge significantly influences the number of animals becoming infected, so the decision to vaccinate should be made swiftly, to allow maximum opportunity for protective immunity to develop.     

From particle attachment to space-filling coral skeletons

Reef-building corals and their aragonite (CaCO₃) skeletons support entire reef ecosystems, yet their formation mechanism is poorly understood. Here we used synchrotron spectromicroscopy to observe the nanoscale mineralogy of fresh, forming skeletons from six species spanning all reef-forming coral morphologies: Branching, encrusting, massive, and table. In all species, hydrated and anhydrous amorphous calcium carbonate nanoparticles were precursors for skeletal growth, as previously observed in a single species. The amorphous precursors here were observed in tissue, between tissue and skeleton, and at growth fronts of the skeleton, within a low-density nano- or microporous layer varying in thickness from 7 to 20 µm. Brunauer-Emmett-Teller measurements, however, indicated that the mature skeletons at the microscale were space-filling, comparable to single crystals of geologic aragonite. Nanoparticles alone can never fill space completely, thus ion-by-ion filling must be invoked to fill interstitial pores. Such ion-by-ion diffusion and attachment may occur from the supersaturated calcifying fluid known to exist in corals, or from a dense liquid precursor, observed in synthetic systems but never in biogenic ones. Concomitant particle attachment and ion-by-ion filling was previously observed in synthetic calcite rhombohedra, but never in aragonite pseudohexagonal prisms, synthetic or biogenic, as observed here. Models for biomineral growth, isotope incorporation, and coral skeletons’ resilience to ocean warming and acidification must take into account the dual formation mechanism, including particle attachment and ion-by-ion space filling.

Coral reef ecosystems cover less than 1% of ocean floors, yet they host 25% of all marine species. In recent years these diverse and important ecosystems have sustained significant declines due to ocean warming and acidification (1–5), and require urgent intervention to survive beyond 2050, when coral reef sediments, including the skeletons of dead corals, will transition from net precipitation to net dissolution (6).Together with coralline algae, bacteria, and other organisms, scleractinian or stony corals deposit a hard skeleton and gradually build up the complex 3D rigid structure of a reef. As the name “coral reef” suggests, compared to other reef-builders, corals are the primary builders of the reef framework structure (7), and the formation of their skeletons is essential to sustain reef ecosystems. Reef-building corals are colonial organisms composed of individual animals, the polyps, which are all genetically identical and connected to one another. In symbiotic corals, which are the majority of reef-building corals, each polyp hosts many endosymbiont dinoflagellate algae from the Symbiodiniaceae family. These algae photosynthesize, supply the polyps with oxygen, glucose, glycerol, and amino acids, and thus provide most of the input the animal needs for its metabolism and the complex skeleton formation mechanisms (8–10).Like many other biominerals, coral skeletons are composites (11) of 97.5 w% aragonite (CaCO₃), 0.07 w% organics (12), and up to 2.5 w% water associated with organics (13). Among the organics, many proteins are involved in skeleton formation (14–16), where they can play both structural and kinetic roles, but the function of only a few proteins is thus far known.The morphology and crystal structure of coral skeletons and their layer-by-layer deposition are well understood (9, 17–19). The aragonite structures include nanoparticulate centers of calcification (CoCs), rich in Mg and organics (20), elongated acicular crystals termed fibers, radiating out of CoCs, and forming plumose spherulites (21), with their crystalline c-axes along the radial direction (21), and randomly oriented crystals called sprinkles, which were only recently observed and were proposed to be proto-fibers: That is, the first nucleated seed of each fiber crystal (22). When sprinkle crystal c-axes are radially oriented they elongate radially to become fibers; when they are not, they can’t grow and thus remain microscopic (0.2 to 20 µm), or they disappear in a coarsening process (22).The mechanism of crystal growth, either ion by ion or particle by particle (23), in coral skeleton is poorly understood and a subject of intense investigation (15, 22, 24–28), especially because it is relevant to understand how corals are responding to climate change, including ocean acidification and warming (1–5, 18, 28). Because the crystal deposition and growth mechanisms are not yet understood, they cannot be used to maximize the impact of interventions and decision making (29, 30). Crystal growth in corals has been thought for a long time to be a purely physicochemical process in which crystals grow one ion at a time from a calcifying fluid (CF) (31, 32). Recently, Mass et al. (33) showed evidence that one species of coral, Stylophora pistillata, deposits its skeleton by attachment of amorphous calcium carbonate (ACC) particles, as previously observed in many other biominerals (34–39). It is unknown if other reef-building corals also form their skeletons by particle attachment, and if particles are the only source of growth material or if ions also attach to growing crystals. In the present work we address these two unknowns.The current understanding is that the particles attaching to form skeletons are first formed intracellularly, within membrane-bound intracellular vesicles. Starting from the CF, located between the biomineralizing cells (calicoblastic cell layer, apical side) and the biomineral growth front, calcium is incorporated into each cell by macropinocytosis, as recently demonstrated by Ganot et al. (see figure 10 in ref. 25). Macropinocytosis produces 350- to 600-nm membrane-bound, intracellular vesicles, which move through the cell cytoplasm and are then exocytosed back into the CF. Such macropinocytosis is ubiquitous in corals and anemones (25). Intracellular vesicles rich in Ca are membrane-bound; that is, they are surrounded by a phospholipid bilayer with proteins that was previously the cell membrane at the apical side. This bilayer surrounds the vesicle, as long as it is intracellular, and then fuses again with the apical membrane when the content of the vesicle is exocytosed and released into the CF. Membrane-bound, intracellular vesicles enriched in calcium and transporting it to the biomineralization site were not only observed in corals and anemones (25), but also in sea urchin embryos (40). Vesicles carrying ACC are extracellular in chicken eggshell formation, but they are also membrane-bound (41).Mass et al. (33) observed a myriad of 400-nm Ca-rich spots in living S. pistillata corals, which could be either solid or liquid. Venn et al. (42) observed pools of CF with elevated pH in living S. pistillata corals. They did not observe such spots in the calicoblastic cell layer. Thus, the intracellular vesicles do not contain elevated-pH liquid droplets. Together, these observations suggest that the intracellular vesicles contain solid ACC particles, not liquid solution droplets, although the exact state of hydration and viscosity remain uncertain. Liquid droplets were the expected result from the liquid–liquid phase separation (LLPS) observed in calcium carbonates grown in vitro by the polymer-induced liquid precursor (PILP) process (43), or predicted by molecular dynamics simulations (44).To investigate how widespread particle attachment is in coral skeleton formation, we analyzed the widest possible variety of species, by selecting at least one representative from each reef-building coral morphology, including branching, massive, encrusting, and table corals (Table 1 and SI Appendix, Table S1). The analysis was done with synchrotron X-ray PhotoEmission Electron Microscopy (PEEM), and component mapping (38) to spatially map and quantify the mineral phases present (33). All of these corals and their forming skeletons were analyzed when they were freshly killed, and their tissues adjacent to the skeleton were preserved to show intratissue precursor phases and to protect the forming skeleton surface.Table 1.The coral skeletons analyzed in Fig. 3

Impact of transmission cycles and vector competence on global expansion and emergence of arboviruses

Arboviruses are transmitted between arthropod vectors and vertebrate host. Arboviral infection in mosquitoes is initiated when a mosquito feeds on a viremic host. Following ingestion of a viremic blood meal by mosquitoes, virus enters midgut along with the blood, infects and replicates in midgut epithelial cells, and then escapes to the hemocoel, from where it disseminates to various secondary organs including salivary glands. Subsequently, when mosquito bites another host, a new transmission cycle is initiated. The midgut and salivary glands act as anatomical barriers to virus infection and escape. These complex interactions between the virus and vector dictate the vector competence. Thus, vector competence reflects the success in overcoming different barriers within the vector. Along with these, other intrinsic factors like midgut microbiota and immune responses, extrinsic factors like temperature and humidity, and genetic factors like vector genotype and viral genotype have been discussed in this review. Recent advancement on novel molecular tools to study vector competence is also included. Different modes of arboviral transmission like horizontal, vertical, and venereal and how these play role in sustenance and emergence of arboviruses in nature are also discussed. These factors can be exploited to reduce the susceptibility of vectors for the viruses, so as to control arboviral diseases to certain extent.     

Infectious bursal disease subviral particles displaying the foot-and-mouth disease virus major antigenic site

An antigen delivery system based on subviral particles formed by the self-assembly of the capsid protein of infectious bursal disease virus and carrying foreign peptides at the top of the projection domain was investigated. We report here the effective insertion of the foot-and-mouth disease virus (FMDV) immunodominant epitope in one of the four external loops of the subviral particles. Out of the two loops tested, one of them tolerated an insert of 12 amino acids without disrupting the subviral particle assembly. The subviral particles reacted with neutralizing FMDV type O1 monoclonal and polyclonal antibodies and elicited a neutralizing antibody response in immunized mice. Furthermore, we found that they have the potential for the detection of FMDV antibodies in a competitive ELISA for diagnostic.     

Amlodipine induced gingival hyperplasia: a rare entity

Drug induced gingival hyperplasia is an uncommon entity. Anticonvulsants, immunosuppressants and calcium channel blockers are often implicated. We report a case of a 52-year old male who developed amlodipine induced gingival hyperplasia. The etiology and treatment modalities are discussed.