Tracing exploitation of egg boons: an experimental study using fatty acids and stable isotopes.

Coordinated spawning of marine animals releases millions of planktonic eggs into the environment, known as egg boons. Eggs are rich in essential fatty acids and may be an important lipid subsidy to egg consumers. Our aim was to validate the application of fatty acid and stable isotope tracers of egg consumption to potential egg consumers and to confirm egg consumption by the selected species. We conducted feeding experiments with ctenophores, crustaceans and fishes. We fed these animals a common diet of Artemia or a commercial feed (Otohime) and simulated egg boons for half of them by intermittently supplementing the common diet with red drum (Sciaenops ocellatus) eggs for 10-94 days. Controls did not receive eggs. Fatty acid profiles of consumers fed eggs were significantly different from those of controls 24 h after the last egg-feeding event. Consumers took on fatty acid characteristics of eggs. In fishes and ctenophores, fatty acid markers of egg consumption did not persist 2-5 days after the last egg-feeding event, but markers of egg consumption persisted in crustaceans for at least 5-10 days. Additionally, consumption of eggs, which had high values of δ15N, led to δ15N enrichment in crustaceans and a fish. We conclude that fatty acids and nitrogen stable isotope can be used as biomarkers of recent egg consumption in marine animals, validating their use for assessing exploitation of egg boons in nature.

Engineering Dynamic Structural Color Pixels at Microscales by Inhomogeneous Strain-Induced Localized Topographic Change.

Structural colors in homogeneous elastomeric materials predominantly exhibit uniform color changes under applied strains. However, juxtaposing mechanochromic pixels that exhibit distinct responses to applied strain remains challenging, especially on the microscale where the demand for miscellaneous spectral information increases. Here, we present a method to engineer microscale switchable color pixels by creating localized inhomogeneous strain fields at the level of individual microlines. Trenches produced by transfer casting from 2.5D structures into elastomers exhibit a uniform structural color in the unstretched state due to interference and scattering effects, while they show different colors under an applied uniaxial strain. This programmable topographic change resulting in color variation arises from strain mismatch between layers and trench width. We utilized this effect to achieve the encryption of text strings with Morse code. The effective and facile design principle is promising for diverse optical devices based on dynamic structures and topographic changes.

Temperature responses vary between riffle beetles from contrasting aquatic environments.

Organisms living in environmentally stable ecosystems are hypothesized to exhibit narrow environmental tolerance ranges; however, previous experiments testing this prediction with invertebrates in spring habitats are equivocal. Here we examined the effects of elevated temperatures on four riffle beetle species (family: Elmidae) native to central and west Texas, USA. Two of these, Heterelmis comalensis and Heterelmis cf. glabra are known to occupy habitats immediately adjacent to spring openings and are thought to have stenothermal tolerance profiles. The other two, Heterelmis vulnerata and Microcylloepus pusillus are surface stream species with more cosmopolitan distributions and are assumed to be less sensitive to variation in environmental conditions. We examined performance and survival of elmids in response to increasing temperatures using dynamic and static assays. Additionally, changes in metabolic rate in response to thermal stress were assessed for all four species. Our results indicated that spring-associated H. comalensis is most sensitive while the more cosmopolitan elmid M. pusillus is least sensitive to thermal stress. However, there were differences in temperature tolerances among the two spring-associated species: H. comalensis had relatively narrow thermal tolerance in comparison to H. cf. glabra. This could be due to differences in the climatic and hydrological conditions in the geographical regions which the respective riffle beetle populations reside. However, despite these differences, H. comalensis and H. cf. glabra showed a dramatic increase in their metabolic rates with increasing temperatures indicating that these species are indeed spring specialists and likely have a stenothermal profile.

Interactions at surface-subterranean ecotones: structure and function of food webs within spring orifices.

Spring orifices are ecotones between surface and subterranean aquatic ecosystems. Invertebrates of different origins (e.g., surface, spring obligate, and subterranean) coexist in these spatially restricted environments, potentially competing for resources. However, processes that allow for population coexistence in these presumably low resource environments are not well understood. We examined invertebrate communities at two spring complexes in Texas, USA and assessed resource use and food web structure at spring orifices using stable isotopes of carbon (δ13C) and nitrogen (δ15N). Using bulk δ13C and δ15N of organisms and potential food sources, we elucidated dietary sources and found that invertebrate communities exhibited resource partitioning and contained two main food chains (periphyton versus terrestrial organic matter [OM]). In both spring complexes, several endemic spring orifice associated and subterranean taxa derived most of their diet from terrestrial OM. Analysis of compound-specific stable isotopes (i.e., δ13C of essential amino acids, EAAs) from two co-occurring elmid species indicated that the endemic spring orifice-associated species (Heterelmis comalensis) derived > 80% of its EAAs from bacteria, whereas the widespread surface species (Microcylloepus pusillus) derived its EAAs from a more equitable mix of bacteria, fungi, and algae. We additionally calculated niche overlap among of several taxonomically related groups (aquatic beetles and amphipods) that co-occur in spring ecotones and posterior probability estimates indicated little to no niche overlap among related species. Results indicate that invertebrates at subterranean-surface aquatic ecotones are partitioning food resources and highlight the importance of connections to riparian zones for persistence of several endemic invertebrates.

Pregnancy associated plasma protein A: An indicator of adverse obstetric outcomes in a South India population.

OBJECTIVE: First trimester aneuploidy screening (FTAS) has become an integral part of antenatal care in most of centers in India. The serum markers used for FTAS are pregnancy-associated plasma protein A (PAPP-A) and beta human chorionic gonadotropin. In the present study, we aimed to assess the role of PAPP-A in specific adverse fetal maternal events. To analyze pregnancy outcomes with low maternal PAPP-A (≤5th percentile) at the FTAS screening test in southern India, and them compared with a control group of >5th percentile value. MATERIALS AND METHODS: A total of 1800 consecutive pregnancies in the first trimester were followed up with PAPP-A levels. The study group consisted 108 subjects, which was compared with a matched control group of 288 subjects. The outcomes considered were spontaneous abortions, fetal anomalies, preterm delivery (PTD), hypertension in pregnancy, intrauterine growth restriction, gestational diabetes, mode of delivery, and birthweight. RESULTS: For our grouped data, the 5th percentile value for PAPP-A was 0.49 multiple of medians, (incidence-6%). The incidence of fetal major anomalies was higher in the study group [odds ratio (OR): 1.87]. The incidence of minor anomalies, gestational diabetes, and hypertensive disorders was higher in the study group but not statistically significant. The total rate of PTDs (OR:2.1), small-for-gestation-age fetuses (OR:2.3), and low birthweight babies (OR- 2.12) was significantly higher in the study group. We found positive likelihood ratio of 1.4 for PTD, 2 for <5th percentile birthweight, and 1.7 for <10th centile birthweight. CONCLUSION: Low PAPP-A pregnancies are at risk of various obstetric complications. Hence, such a pregnancy should have closer surveillance. Further research work on intervention strategy is needed.

Self-assembling peptide nanofibers containing phenylalanine for the controlled release of 5-fluorouracil.

The study shows that RADA-F6 peptide with pH-responsive self-assembling nature can be effectively used as a drug delivery system for the sustained release of a potent anticancer drug 5-fluorouracil (5-FU) at basic pH. As 5-FU contains the aromatic pyrimidine ring, RADA-F6 system is suitable for entrapping an aromatic drug due to effective π-π stacking with phenylalanine and be able to show better controlled release behavior. The stability and controlled release nature of RADA-F6 in different conditions followed by 5-FU entrapment at in silico conditions was confirmed by molecular dynamics simulation taking RADA-16 as control. Cytotoxicity of the drug-loaded RADA-F6 was measured by MTT assay and cellular uptake by confocal microscopy. Physicochemical characterization and further Western blot analysis and flow cytometric studies confirm that RADA-F6 can be successfully used as an efficient vector for pH-sensitive, controlled 5-FU delivery system.

Intramuscular hemangioma of the masseter muscle- a case report and review of literature.

INTRODUCTION: Intramuscular hemangioma, is a distinctive type of vascular tumor occurring within the skeletal muscle. Most IMH are located in the lower extremity, particularly in the muscles of the thigh and rarely in head and neck region. PRESENTATION OF CASE: 35 years old male reported with a swelling in the left cheek region since 3 years. Clinical and radiological evaluation leads to the diagnosis of Intramuscular hemangioma. Surgical excision was performed and histopathology confirmed the diagnosis. DISCUSSION: Hemangiomas of skeletal muscle represent 0.8% of all benign vascular neoplasm Welsch and Hengerer, 1980 [4]. Of these 13.8% occur in the head and neck region, with the masseter muscle being the most common site, followed by the trapezius and sternocleidomastoid muscles respectively. The lesions previously described as deep infiltrating angiolipomas have now been recognized by the WHO as intramuscular hemangiomas. numerous theories proposed for ethiopathogenisis of vascular lesions have been discussed. CONCLUSION: In conclusion, angiolipomas are rare in the head and neck region, and it should be considered in the differential diagnosis of masses in these regions. Proper radiological and clinical examination will reveal the type of vascular lesion. Excellent results can be obtained with timely management and good surgical skills.

The Versatility in the Use of Buccal Fat Pad in the Closure of Oro-antral Fistulas.

INTRODUCTION: Oroantral communications (OAC) are probable surgical complications of dentoalveolar procedures. OACs 2 mm in diameter or smaller are likely to close spontaneously without the need for any surgical intervention. However, OACs 3 mm in diameter or larger, or OACs associated with maxillary or periodontal inflammation, may persist, and surgical closure is recommended. Various surgical techniques have been suggested for the closure of oroantral defects. CASE DETAILS: We have found the technique of two layer closure with buccal fat pad (BFP) and buccal mucoperiosteum quite useful for closure of chronic Oroantral fistula (OAF) and this article reports a case of OAF in the left first molar region of a 50 year old male, which has been closed successfully with this technique. CONCLUSION: Buccal fat pad is a pedicled locally available flap which has its own blood supply and hence can be used with great efficacy in closure of OAF. This paper aims to elaborate the surgical details of this technique and its usefulness in closure of chronic OAF.

Restriction Profiling of 23S Microheterogenic Ribosomal Repeats for Detection and Characterizing of E. coli and Their Clonal, Pathogenic, and Phylogroups.

Correlating ribosomal microheterogenicity with unique restriction profiles can prove to be an efficacious and cost-effective approach compared with sequencing for microbial identification. An attempt to peruse restriction profiling of 23S ribosomal assemblage was ventured; digestion patterns with Bfa I discriminated E. coli from its colony morphovars, while Hae III profiles assisted in establishing distinct clonal groups. Among the gene pool of 399 ribosomal sequences extrapolated from 57 E. coli genomes, varying degree of predominance (I > III > IV > II) of Hae III pattern was observed. This was also corroborated in samples collected from clinical, commensal, and environmental origin. K-12 and its descendants showed type I pattern whereas E. coli-B and its descendants exhibited type IV, both of these patterns being exclusively present in E. coli. A near-possible association between phylogroups and Hae III profiles with presumable correlation between the clonal groups and different pathovars was established. The generic nature, conservation, and barcode gap of 23S rRNA gene make it an ideal choice and substitute to 16S rRNA gene, the most preferred region for molecular diagnostics in bacteria.

Citrate-based Biodegradable Injectable hydrogel Composites for Orthopedic Applications.

Previous studies have confirmed that natural bone apatite crystals are bound with citrate-rich molecules. Citrates on apatite crystals impact bone development and its load-bearing function. However, such understanding has never been translated into bone biomaterials design. Herein, a first citrate-based injectable composite material for orthopedic applications is developed based on our recently developed biodegradable poly(ethylene glycol) maleate citrate (PEGMC) and hydroxyapatite (HA). PEGMC contains rich carboxylic groups that could chelate with calcium-containing HA thus facilitating polymer/HA interactions, similar to natural citrate-bound apatite crystal. The crosslinking of poly(ethylene glycol) diacrylate (PEGDA) with PEGMC/HA composites allows an addition control over degradation and mechanical properties of the crosslinked PEGMC/HA (CPEGMC/HA) composites. CPEGMC/HA composite can serve as an ideal injectable cell carrier as confirmed by the enhanced DNA content, ALP activity, and calcium production through a human fetal osteoblast encapsulation study. Ex vivo study on porcine femoral head demonstrated that PEGMC/HA is a potentially promising injectable biodegradable bone material for the treatment of osteonecrosis of the femoral head. Development of biodegradable citrate-based injectable PEGMC/HA composite is an initial step for the development of the next generation of bone tissue engineering and orthopedic biomaterials.

A Rheological Study of Biodegradable Injectable PEGMC/HA Composite Scaffolds.

Injectable biodegradable hydrogels, which can be delivered in a minimally invasive manner and formed in situ, have found a number of applications in pharmaceutical and biomedical applications, such as drug delivery and tissue engineering. We have recently developed an in situ crosslinkable citric acid-based biodegradable poly (ethylene glycol) maleate citrate (PEGMC)/hydroxyapatite (HA) composite, which shows promise for use in bone tissue engineering. In this study, the mechanical properties of the PEGMC/HA composites were studied in dynamic linear rheology experiments. Critical parameters such as monomer ratio, crosslinker, initiator, and HA concentrations were varied to reveal their effect on the extent of crosslinking as they control the mechanical properties of the resultant gels. The rheological studies, for the first time, allowed us investigating the physical interactions between HA and citric acid-based PEGMC. Understanding the viscoelastic properties of the injectable gel composites is crucial in formulating suitable injectable PEGMC/HA scaffolds for bone tissue engineering, and should also promote the other biomedical applications based on citric acid-based biodegradable polymers.

Citric acid-derived in situ crosslinkable biodegradable polymers for cell delivery.

Herein, we report a first citric acid (CA)-derived in situ crosslinkable biodegradable polymer, poly(ethylene glycol) maleate citrate (PEGMC). The synthesis of PEGMC could be carried out via a one-pot polycondensation reaction without using organic solvents or catalysts. PEGMC could be in situ crosslinked into elastomeric PPEGMC hydrogels. The performance of hydrogels in terms of swelling, degradation, and mechanical properties were highly dependent on the molar ratio of monomers, crosslinker concentration, and crosslinking mechanism used in the synthesis process. Cyclic conditioning tests showed that PPEGMC hydrogels could be compressed up to 75% strain without permanent deformation and with negligible hysteresis. Water-soluble PEGMC demonstrated excellent cytocompatibilty in vitro. The degradation products of PPEGMC also showed minimal cytotoxicity in vitro. Animal studies in rats clearly demonstrated the excellent injectability of PEGMC and degradability of the in situ-formed PPEGMC. PPEGMC elicited minimal inflammation in the early stages post-injection and was completely degraded within 30 days in rats. In conclusion, the development of CA-derived injectable biodegradable PEGMC presents numerous opportunities for material innovation and offers excellent candidate materials for in situ tissue engineering and drug delivery applications.