External Tissues Research Articles

Pollen analyses for pollination research, unacetolyzed pollen

Pollinators feed on the pollen, nectar, and other plant exudates that are associated with flowers. As a result of this feeding activity, pollen becomes attached to them. Analysis of this pollen can reveal what they eat, their dispersal patterns in and around cropping systems, and their role in pollination. However, finding pollen on and or in a pollinator depends on the technique used to recover pollen. Two very easy techniques are described in detail that have been used to recover pollen from a variety of pollinators including beneficial and harmful insects, spiders, bats, and other pollinators. These techniques can be used to recover pollen from internal tissues (gut, alimentary canal, crop, etc.), external tissues (proboscis, legs, eyes, etc.), or both. By using the proper technique, better pollen recovery can be made and thus better data can be obtained about the pollinators, the foods they eat, the plants they pollinate, their migration routes and source zones.

Expression of Reversion-Inducing Cysteine-Rich Protein with Kazal Motifs and Matrix Metalloproteinase 9 in Middle Ear Squamous Cell Carcinoma

Objective: Reversion-inducing cysteine-rich protein with kazal motifs (RECK) may negatively regulate matrix metalloproteinase 9 (MMP9) activity and suppress tumor invasion and metastasis. The aim of this study was to investigate whether RECK and MMP were involved in regulating middle ear carcinoma invasion and metastasis. Methods: RECK and MMP9 were measured in 30 middle ear squamous cell carcinoma tissues and 20 adjacent normal external ear canal skin tissues using immunohistochemical analysis. Results: The positive rate of RECK expression in the middle ear squamous cell carcinoma was much lower than that in the normal external ear canal skin. In contrast, the positive rate of MMP9 expression was higher in middle ear squamous cell carcinoma tissue than that in normal external ear canal skin tissue. The expressions of RECK and MMP9 were correlated with the histological grade and tumor stage, but not with patient age or gender. Conclusions: RECK and MMP9 are involved in middle ear squamous cell carcinoma and may serve as markers to evaluate progression and metastasis.

Estimation of genetic parameters and gains for color traits of strawberry

An investigation of strawberry (Fragaria × ananassa Duch.) fruit and juice color dimensions (L* a* b*) was conducted to estimate genetic parameters and determine breeding strategies for improving fruit color in the University of Florida strawberry breeding population. The genetic analysis was conducted using clonally replicated seedlings from a factorial mating design with additional biparental crosses and was evaluated in two locations. Substantial additive and non-additive genetic variation was described for most traits. Low genotype by environment interactions indicate that color evaluations may be conducted in either of the two test locations. Consistent with previous reports, genetic correlations indicated that internal and external fruit colors are under separate genetic control. Colorimeter a* and L* values described the same information for internal color in that internal flesh that was darker in color also appeared more red. A method was developed to reliably measure a* and L* for small (2 ml) samples of strawberry juice. Juice a* had significant genetic correlations with internal a* and may be used as a correlated trait to improve the internal redness of the fruit. However, pigments from the external tissues of the fruit appear to also impact the L* value of strawberry juice, complicating the effects of selection on juice color traits.

The Cytotoxic Effects of Preserved and Preservative-Free Prostaglandin Analogs on Human Corneal and Conjunctival Epithelium In Vitro and the Distribution of Benzalkonium Chloride Homologs in Ocular Surface Tissues In Vivo

Purpose: To investigate the cytotoxicity of benzalkonium chloride (BAC)-containing ophthalmic solutions of prostaglandin analogs (latanoprost, travoprost, bimatoprost, and preservative-free (PF) tafluprost), BAC mixture (BACmix) and BAC homologs with different alkyl chain lengths using human corneal epithelial (HCE) and conjunctival epithelial (IOBA-NHC) cell cultures. The distribution of BAC homologs in rabbit ocular surface tissues in vivo was examined.Methods: The cells were exposed for one hour to prostaglandin analogs, BACmix and three homologs. Cytotoxicity was assessed with the WST-1 and lactate dehydrogenase (LDH) assays for cellular viability and cell membrane integrity. BAC 0.02% solution was instilled on the rabbit eye daily for 14 days and the concentrations of BAC homologs in external ocular tissues were determined.Results: The order of decreasing cytotoxicity in the WST-1 test was latanoprost ≥ travoprost > bimatoprost ≥ PF tafluprost. IOBA-NHC cells were more sensitive than HCE cells. In HCE, only latanoprost diluted to 10% increased LDH leakage. In IOBA-NHC, LDH leakage was statistically significant with 3–10% travoprost and 10% latanoprost. The order of decreasing cytotoxicity of preservatives was C14 > C12 > BACmix > C16 in HCE and C12 > C14 > BACmix > C16 in IOBA-NHC. Following treatment with BAC 0.02% solution, the amounts of BAC-C12, -C14 and -C16 in rabbit cornea and conjunctiva, respectively were: 0.37 ± 0.08 and 2.64 ± 0.27 ng/mg; 0.42 ± 0.07 and 4.77 ± 0.43 ng/mg; 0.04 ± 0.01 and 0.54 ± 0.05 ng/mg.Conclusions: The cytotoxic effects of latanoprost, travoprost, and bimatoprost were dependent on the BAC concentration in their formulations. BACmix was cytotoxic at the concentrations above those corresponding to 0.001% BAC in ophthalmic medications. PF tafluprost was the least toxic of the drugs tested. Within studied BAC homologs, those with longer alkyl chain and higher lipophility penetrated effectively into rabbit external ocular tissues.

External tissue support and fluid–structure simulation in blood flows

The objective of this work is to address the formulation of an adequate model of the external tissue environment when studying a portion of the arterial tree with fluid-structure interaction. Whereas much work has already been accomplished concerning flow and pressure boundary conditions associated with truncations in the fluid domain, very few studies take into account the tissues surrounding the region of interest to derive adequate boundary conditions for the solid domain. In this paper, we propose to model the effect of external tissues by introducing viscoelastic support conditions along the artery wall, with two-possibly distributed-parameters that can be adjusted to mimic the response of various physiological tissues. In order to illustrate the versatility and effectiveness of our approach, we apply this strategy to perform patient-specific modeling of thoracic aortae based on clinical data, in two different cases and using a distinct fluid-structure interaction methodology for each, namely an Arbitrary Lagrangian-Eulerian (ALE) approach with prescribed inlet motion in the first case and the coupled momentum method in the second case. In both cases, the resulting simulations are quantitatively assessed by detailed comparisons with dynamic image sequences, and the model results are shown to be in very good adequacy with the data.

Advancing environmental toxicology through chemical dosimetry: External exposures versus tissue residues

The tissue residue dose concept has been used, although in a limited manner, in environmental toxicology for more than 100 y. This review outlines the history of this approach and the technical background for organic chemicals and metals. Although the toxicity of both can be explained in tissue residue terms, the relationship between external exposure concentration, body and/or tissues dose surrogates, and the effective internal dose at the sites of toxic action tends to be more complex for metals. Various issues and current limitations related to research and regulatory applications are also examined. It is clear that the tissue residue approach (TRA) should be an integral component in future efforts to enhance the generation, understanding, and utility of toxicity testing data, both in the laboratory and in the field. To accomplish these goals, several key areas need to be addressed: 1) development of a risk-based interpretive framework linking toxicology and ecology at multiple levels of biological organization and incorporating organism-based dose metrics; 2) a broadly applicable, generally accepted classification scheme for modes/mechanisms of toxic action with explicit consideration of residue information to improve both single chemical and mixture toxicity data interpretation and regulatory risk assessment; 3) toxicity testing protocols updated to ensure collection of adequate residue information, along with toxicokinetics and toxicodynamics information, based on explicitly defined toxicological models accompanied by toxicological model validation; 4) continued development of residue-effect databases is needed ensure their ongoing utility; and 5) regulatory guidance incorporating residue-based testing and interpretation approaches, essential in various jurisdictions.

Ethnobotanical study of Sabalan district in Ardabil province of Iran

The present study was carried out to assess and document ethnobotanical knowledge of the plants of Sabalan district in Ardabil Province, as the area has diverse flora and high ethnobotanical potential. Medicinal plants of Sabalan were studied through collections of plant specimens and by interviewing local informants from several villages. For Each plant species the scientific and vernacular name, the parts of the plants used, specific medicinal uses, modes of preparation and administration and way of obtaining them were listed. Plants were used mainly for diseases of digestive tract, infectious diseases of external tissues, respiratory disorders, cardiovascular diseases, urinary diseases and indigenous people use some of them as food. After clinical and experimental tests and phyochemical analysis, these Medicinal plants may be broadly applied in modern medicine.

Implants as drug delivery devices for the treatment of eye diseases

The treatment of diseases affecting the posterior segment of the eye is limited by the difficulty in transporting effective doses of drugs to the vitreous, retina, and choroid. Topically applied drugs are poorly absorbed due to the low permeability of the external ocular tissues and tearing. The blood-retina barrier limits drug diffusion from the systemic blood to the posterior segment, thus high doses of drug are needed to maintain therapeutic levels. In addition, systemic side effects are common. Intraocular injections could be an alternative, but the fast flowing blood supply in this region, associated with rapid clearance rates, causes drug concentration to quickly fall below therapeutic levels. To obtain therapeutic levels over longer time periods, polymeric sustained-drug release systems implanted within the vitreous are being studied for the treatment of vitreoretinal disorders. These systems are prepared using different kinds of biodegradable or non-biodegradable polymers. This review aims to demonstrate the main characteristics of these drug delivery implants and their potential for clinical application.

SU‐GG‐J‐131: Immobilization Bed for Multi‐Modality Image Registration

Purpose: To construct an immobilization bed for mice that will allow for longitudinal multimodality imaging studies as well as conformai radiotherapy. The bed must be capable of both intra‐examination immobilization as well as inter‐examination positioning reproducibility. It must also accommodate mice of various sizes and facilitate image registration. Method and Materials: An immobilization bed was manufactured from clear acrylic to enable use with optical imaging modalities. Measurements of multiple mice of various ages and species were made in order to find the optimal size for the bed and for the restrainer pegs. The pegs were placed in stationary positions that effectively immobilize the majority of mice and enable high throughput imaging by avoiding adjustments for every mouse. The pegs were placed such that the front legs of the subject are each placed between two pegs as are the hind legs. An additional set of pegs were placed laterally and posteriorly to guide the hind legs in a reproducible direction. Na‐22 PET/CT fiducials were put into the pegs at unique depths to provide a three‐dimensional reference to allow fast and accurate image registration. Results: An average sized nude mouse without anesthesia (a worst case scenario test) was only capable of 3mm of movement vertically. Serial CT scans in‐between which the bed was moved showed no shifts in bony anatomy or external soft tissues. When PET and CT scans were registered without use of the fiducials, the heart was misplaced medially by ∼1mm and inferiorly by ∼1mm. The fiducials have allowed for accurate CT registration. Conclusion: The bed is effective in immobilization and image registration. The use of this bed will be enable the elucidation of minute changes in the PET scans and the use of molecular imaging data for radiation treatment planning and followup.

Chemical defenses of tunicates of the genus Aplidium from the Weddell Sea (Antarctica)

Predation and competition are important factors structuring Antarctic benthic communities and are expected to promote the production of chemical defenses. Tunicates are subject to little predation, and this is often attributed to chemical compounds, although their defensive activity has been poorly demonstrated against sympatric predators. In fact, these animals, particularly the genus Aplidium, are rich sources of bioactive metabolites. In this study, we report the natural products, distribution and ecological activity of two Aplidium ascidian species from the Weddell Sea (Antarctica). In our investigation, organic extracts obtained from external and internal tissues of specimens of A. falklandicum demonstrated to contain deterrent agents that caused repellency against the Antarctic omnivorous predator, the sea star Odontaster validus. Chemical analysis performed with Antarctic colonial ascidians Aplidium meridianum and Aplidium falklandicum allowed the purification of a group of known bioactive indole alkaloids, meridianins A-G. These isolated compounds proved to be responsible for the deterrent activity.

Polyphenol content and antioxidant capacity in organic and conventional plant foods

Fruit and vegetable intake is associated with lower risk of chronic diseases as a result of consumption of antioxidant substances. Organic foods are thought to have higher antioxidant capacity, because this form of agricultural management could induce synthesis of secondary compounds such as polyphenols. The objective of this work is to evaluate polyphenol content and antioxidant capacity in organically (OG) and conventionally (CV) grown fruits and vegetables, as well as in different parts of the plants. Soluble and hydrolysable polyphenols were quantified by Folin–Ciocalteu reagent, and the antioxidant capacity was measured by the DPPH radical method. The results showed that organic fruits tend to have higher hydrolysable polyphenol contents than conventional ones, with values being 11.5% in orange peels, to 72.6% in papaya peels, higher for hydrolysable polyphenols. Fruit peels also showed higher concentration of polyphenols than pulp, reaching, for bananas and tangerines, twice the amount found in pulps, which reflected in higher antioxidant capacity. Polyphenol content and antioxidant capacity varied among organic and conventional vegetables with no prevalence from either agricultural type. This study suggests that the effect of organic practices results in different effect patterns according to the plant species analysed, with fruits being more susceptible to the induction of polyphenol synthesis, and the greatest accumulation of polyphenols in external plant tissues. In general, organic agriculture results in food products with similar or slightly higher polyphenol content and antioxidant capacity.

Practical approach to steroid 5alpha-reductase type 2 deficiency

The aim of this article is to review the literature on steroid 5alpha-reductase type 2 deficiency (5α-RD2) to provide clinicians with information to guide their management of patients with this disorder. The 5alpha-reductase type 2 is encoded by the 5alpha-reductase type 2 gene (SRD5A2) on chromosome 2 and is predominantly expressed in external genital tissues and the prostate. Mutations of the SRD5A2 gene leads to an uncommon autosomal recessive disorder affecting sexual differentiation in individuals with 46,XY karyotype; their phenotype can range from almost normal female structures to a distinct male phenotype with ambiguous genitalia at birth. These phenotypes result from impaired conversion of testosterone to dihydrotestosterone due to mutations in the SRD5A2 gene. Patients exhibit virilization at puberty without breast development, which is often accompanied by gender identity change from female to male. More than 40 mutations have been reported in all five exons of the SRD5A2 gene. Phenotype-genotype correlations for 5α-RD2 have not been well established. The newborn phenotypes of male pseudohermaphrodites with 5α-RD2, partial androgen insensitivity syndrome (PAIS), or 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) enzyme deficiency may be indistinguishable. We conclude that steroid 5α-RD2 should be included in the differential diagnosis of newborns with 46,XY DSD. It is important that the diagnosis be made in infancy by biochemical and molecular studies before gender assignment or any surgical intervention because these patients should be considered males at birth.

Genetic and Physiological Characterization of the Arlequin Insertional Mutant Reveals a Key Regulator of Reproductive Development in Tomato

The genetic and phenotypic characterization of a new tomato (Solanum lycopersicum) insertional mutant, Arlequin (Alq) is reported. Alq mutant plants were affected in reproductive development and their sepals were homeotically converted into fleshy fruit-like organs. Molecular analysis demonstrated that a single copy of T-DNA was present in the mutant genome while genetic analysis confirmed that the mutant phenotype co-segregated with the T-DNA insertion and was inherited as a monogenic semi-dominant trait. The histological and scanning electron microscope analyses revealed cell identity changes in both external and internal tissues of Alq sepals. Flowers developed by Alq homozygous plants showed a severe mutant phenotype, since after fruit set, not only did the sepals become succulent but they also followed a ripening pattern similar to that of normal fruits. From a metabolic viewpoint, Alq sepals also behaved like a fruit, as they acquired the properties of a sink that acted alternatively and independently to the fruit. In fact, expression of regulatory genes controlling tomato fruit ripening was detected in Alq sepals at similar levels to those observed in mature fruits. Furthermore, the Alq mutation inhibited the development of the abscission zone in tomato flowers indicating that the JOINTLESS gene is regulated by ALQ. Results from the genetic and developmental characterization of the Alq tomato mutant suggest that the ALQ gene participates in the regulatory pathway controlling fruit ripening of tomato.

Comparison of gene expression profiling between bovine subcutaneous and intramuscular adipose tissues by serial analysis of gene expression

The deposition of intramuscular adipose fat is an important factor in the quality of beef, particularly in Korean cattle and Japanese cattle. A better understanding of the differential mechanisms regulating the deposition and release of fat between intramuscular and external adipose tissues, particularly subcutaneous adipose tissues, would prove vital in understanding the deposition of intramuscular fat. A SAGE (serial analysis of gene expression) method was used to identify functionally active genes in adipose tissues and to compare the global gene expression profile between the subcutaneous and the intramuscular adipose tissues in Korean cattle. We detected 11268 tags, representing 3761 transcripts in the SAGE library of the subcutaneous adipose tissues. We detected 10830 tags, representing 2918 transcripts in the intramuscular adipose tissues. Comparison of gene expression patterns between subcutaneous adipose tissues and intramuscular adipose tissues revealed that 82 genes were differentially expressed at >2-fold levels. Among them, expression levels of 50 genes were higher in subcutaneous adipose tissues compared with intramuscular tissues, whereas those of 32 genes were higher in intramuscular adipose tissues. The genes that displayed >2-fold higher expression in subcutaneous adipose tissues included secreted protein acidic and rich in cysteine, annexin II, thyroid hormone receptor interactor 1, ferritin heavy chain polypeptide 1, cofilin, diacylglycerol O-acyltransferase and thymosin beta 4. Those that showed >2-fold higher expression levels in intramuscular adipose tissues included troponin t3, heat shock 70 kDa protein 1 and NMT2 (N-myristoyltransferase 2). Expression patterns of NMT2 and troponin t3 genes were examined during differentiation of 3T3-LI preadipocytes. NMT2 gene was actively expressed at both the growing stage of preadipocytes and the initial stage of differentiation of 3T3-L1 adipocytes, but its expression was reduced at the active stage of adipocyte differentiation. Troponin t3 gene was not expressed at the growing stage of preadipocyte, but it was actively expressed during differentiation of adipocytes. This implies that troponin t3 may play a positive role in intramuscular fat deposition of beef. Our SAGE experiment provides a differential gene expression profile in subcutaneous and intramuscular adipose tissues of Korean cattle. This information will be useful in developing method(s) to produce high-marble beef.

Tight junction modulator and drug delivery

Recent progress in pharmaceutical technology based on genomic and proteomic research has provided many drug candidates, including not only chemicals but peptides, antibodies and nucleic acids. These candidates do not show pharmaceutical activity without their absorption into systemic flow and movement from the systemic flow into the target tissue. Epithelial and endothelial cell sheets play a pivotal role in the barrier between internal and external body and tissues. Tight junctions (TJs) between adjacent epithelial cells limit the movement of molecules through the intercellular space in epithelial and endothelial cell sheets. Thus, a promising strategy for drug delivery is the modulation of TJ components to allow molecules to pass through the TJ-based cellular barriers. In this review, we discuss recent progress in the development of TJ modulators and the possibility of absorption enhancers and drug-delivery systems based on TJ components.

Impact of durum wheat milling on deoxynivalenol distribution in the outcoming fractions

The milling behaviour of two naturally infected samples of durum wheat grain with contrasting levels of mycotoxins was studied. Although the two samples showed a similar milling behaviour, an increase of ∼20% in deoxynivalenol (DON) levels was found in semolina from the sample containing the higher level of mycotoxin. However, even if the highest concentration of DON was found in fractions originating from the grain outer layers, the mycotoxin contamination in semolina and flours were not related to the amount of two compounds (ash or phytic acid) used to monitor these external tissues. The presence of the trichothecene-producing fungi in the inner-most semolina fraction was also shown using specific DNA primers and PCR amplification. Comparison of DON concentrations in the feed stock and corresponding output at each milling step or grinding of semolina fractions followed by sizing showed that concentration of mycotoxin occurs in the finest particles at the first processing steps. Therefore, DON contamination of milling fractions is not simply due to the presence of peripheral grain tissues.

Chitosan based nanocarriers for indomethacin ocular delivery

Two different chitosan (CS) nanocarriers namely nanoparticles and nanoemulsion were developed to prolong Indomethacin (IM) precorneal residence time and to improve its ocular bioavailability the main limitations in its management of post-operative inflammation and intraocular irritation after cataract extraction. CS-nanoparticles were developed by modified ionic gelation of CS with tripolyphosphate while nanoemulsion was prepared by spontaneous emulsification technique. Transmission electron microscopy revealed regular well-identified spherical shape. The nanoparticles had a mean size of 280 nm, a zeta potential of + 17 mV and high loading efficiency of 84.8 % while the mean size of nanoemulsion was affected by the nature of the surfactant used and varies between 220-690 nm. In vitro release studies, performed under sink conditions, revealed small initial burst release during the first hour followed by slow gradual drug release of 76 and 86% from nanoparticles and nanoemulsion respectively during a 24 h period. In vivo studies and histopathological examination revealed that eyes of rabbits treated with nanoemulsion showed clearer healing of corneal chemical ulcer with moderate effective inhibition of polymorph nuclear leukocytic infiltration (PMNLs) compared with nanoparticles preparation. Moreover, following topical instillation of CS-nanoemulsion to rabbits, it was possible to achieve therapeutic concentration of IM in the cornea through out the duration of the study and fairly high IM level in inner ocular structure, aqueous humor. These levels were significantly higher than those obtained following instillation of IM solution. Therefore, CS nanocarriers developed in this study were able to contact intimately with the cornea providing slow gradual IM release with long-term drug level thereby increasing delivery to both external and internal ocular tissues.

Stealth tactics of galling parasites and their potential indirect effects

Stealth tactics of galling parasites and their potential indirect effects

Influence of aqueous 1-methylcyclopropene concentration, immersion duration, and solution longevity on the postharvest ripening of breaker-turning tomato ( Solanum lycopersicum L.) fruit

The influence of aqueous 1-methylcyclopropene (1-MCP) concentration, immersion duration, and solution longevity on the ripening of early ripening-stage tomato ( Solanum lycopersicum L.) has been investigated. Tomato fruit at the breaker-turning stage were fully immersed in aqueous 1-MCP at 50, 200, 400 and 600 μg L −1 for 1 min, quickly dried, and then stored at 20 °C. Ethylene production, respiration, surface color development, and rate of accumulation of lycopene and polygalacturonase (PG) activity were suppressed and/or delayed in fruit exposed to aqueous 1-MCP. Suppression of ripening was concentration dependent, with maximum inhibition in response to 1 min immersion occurring at concentrations of 400 and 600 μg L −1. Climacteric ethylene peaks were delayed approximately 6, 7, and 9 d and respiration was strongly suppressed in fruit treated with aqueous 1-MCP at 200, 400, and 600 μg L −1, respectively, compared with control fruit. Fruit firmness, lycopene content, PG activity, and surface hue of fruit treated at the three higher levels remained strongly suppressed compared with control. Skin hue values and pericarp lycopene content in response to treatment at the subthreshold 50 μg L −1 provided evidence for differential ripening suppression in external versus internal tissues. Maximum delay of softening and surface color development in response to 50 μg L −1 aqueous 1-MCP occurred following immersion periods of between 6 and 12 min. Factors affecting fruit penetration by aqueous 1-MCP and mechanisms contributing to recovery from 1-MCP-induced ripening inhibition are discussed.

The influence of plant anatomy on oviposition and reproductive success of the omnivorous bug Orius insidiosus

The mechanisms whereby the reproductive behaviour and success of omnivorous insects are influenced by plant characteristics are poorly understood. We examined how the oviposition behaviour of zoophytophagous Orius insidiosus and the subsequent longevity of its progeny are influenced by the physical structure and internal anatomy of five plant species. Female O. insidiosus oviposit into plant species with the thinnest layers of epidermal and collenchyma cells, a decision that is significantly correlated with the survival of their offspring. Once a plant species is chosen, the female mainly bases her oviposition decisions on epidermal thickness and the surface density of hair-like appendages on the plants. That females laid more eggs and nymphs survived longer on plants with thinner external tissues suggest that the mechanisms that drive female oviposition decisions have evolved such that optimal plant-based resources are available for the females' progeny. Microscopic examination of plant anatomical features revealed that vascular and cellular tissues are fully accessible to the piercing–sucking mouthparts of the developing insects, suggesting that multiple sources of plant nutrients are available to this omnivore. The ecological implications of plant-based contributions to O. insidiosus fitness are discussed.