Anthocyanin Tissue Bioavailability in Animals: Possible Implications for Human Health. A Systematic Review.

Anthocyanins (ACNs) are promising health-enhancing phenolic compounds. We focus on ACN animal tissue bioavailability to provide an evidentiary link between tissue ACNs and their associated health properties. We performed a systematic review of electronic libraries; 279 results were retrieved, and 13 publications met inclusion criteria. Extracted information included animal model employed, administration route, doses, analysis method, and ACN concentration values in tissues. Total ACN concentrations were detected in mice kidney (2.17 × 105 pmol/g), liver (1.73 × 105 pmol/g), heart (3.6 × 103 pmol/g), and lung (1.16 × 105 pmol/g); and in pig brain (6.08 × 103 pmol/g). ACNs showed a predominance of parent ACNs in long-term experiments versus an ACN metabolite predominance in short-term experiments. ACNs detected in animal tissues, such as cyanidin-3-glucoside, suggest it may have an important role in human health. This information could be useful to determine proper ACN-intake biomarkers in biological samples in futures studies.

Tentacle extract from the jellyfish Cyanea capillata increases proliferation and migration of human umbilical vein endothelial cells through the ERK1/2 signaling pathway.

Wound healing is a complex biological process, and current research finds that jellyfish have a great capacity for promoting growth and healing. However, the underlying mechanisms remain unclear. Thus, this study was conducted to investigate the molecular mechanisms and effects of a tentacle extract (TE) from the jellyfish Cyanea capillata (C. capillata) on cell proliferation and migration in human umbilical vein endothelial cells (HUVECs). First, our results showed that TE at the concentration of 1 µg/ml could promote cell proliferation over various durations, induce a transition of the cells from the G1-phase to the S/G2-phase of the cell cycle, and increase the expression of cell cycle proteins (CyclinB1 and CyclinD1). Second, we found that TE could activate the PI3K/Akt, ERK1/2 and JNK MAPK signaling pathways but not the NF-κB signaling pathway or the apoptosis signaling cascade. Finally, we demonstrated that the TE-induced expression of cell cycle proteins was decreased by ERK1/2 inhibitor PD98059 but not by PI3K inhibitor LY294002 or JNK inhibitor SP600125. Similarly, the TE-enhanced migration ability of HUVECs was also markedly attenuated by PD98059. Taken together, our findings indicate that TE-induced proliferation and migration in HUVECs mainly occurred through the ERK1/2 MAPK signaling pathway. These results are instructively important for further research on the isolation and purification of growth-promoting factors from C. capillata and are hopeful as a means to improve human wound repair in unfavorable conditions.

Anti-malarial and anti-inflammatory effects of Gleichenia truncata mediated through inhibition of GSK3ß.

Gleichenia truncata is a highland fern from the Gleicheniaceae family known for its traditional use among indigenous communities in Asia to treat fever. The scientific basis of its effect has yet to be documented. A yeast-based kinase assay conducted in our laboratory revealed that crude methanolic extract (CME) of G. truncata exhibited glycogen synthase kinase-3 (GSK3)-inhibitory activity. GSK3ß is now recognized to have a pivotal role in the regulation of inflammatory response during bacterial infections. We have also previously shown that lithium chloride (LiCl), a GSK3 inhibitor suppressed development of Plasmodium berghei in a murine model of malarial infection. The present study is aimed at evaluating G. truncata for its anti-malarial and anti-inflammatory effects using in vivo malarial and melioidosis infection models respectively. In a four-day suppressive test, intraperitoneal injections of up to 250 mg/kg body weight (bw) G. truncata CME into P.berghei-infected mice suppressed parasitaemia development by >60%. Intraperitoneal administration of 150 mg/kg bw G. truncata CME into Burkholderia pseudomallei-infected mice improved survivability by 44%. G. truncata CME lowered levels of pro-inflammatory cytokines (TNF-α, IFN-γ) in serum and organs of B. pseudomallei-infected mice. In both infections, increased phosphorylations (Ser9) of GSK3ß were detected in organ samples of animals administered with G. truncata CME compared to controls. Taken together, results from this study strongly suggest that the anti-malarial and anti-inflammatory effects elicited by G. truncata in part were mediated through inhibition of GSK3ß. The findings provide scientific basis for the ethnomedicinal use of this fern to treat inflammation-associated symptoms.

Preventive effects of the polysaccharide of Larimichthys crocea swim bladder on carbon tetrachloride (CCl4)-induced hepatic damage.

The aim of the present study was to determine the preventive effects of the polysaccharide of Larimichthys crocea swim bladder (PLCSB) on CCl4-induced hepatic damage in ICR mice. The in vitro preventive effects of PLCSB on CCl4-induced liver cytotoxic effect were evaluated in BRL 3A rat liver cells using the MTT assay. The serum levels of AST, ALT, and LDH in mice were determined using commercially available kits. The levels of IL-6, IL-12, TNF-α, and IFN-γ were determined using ELISA kits. The pathological analysis of hepatic tissues was performed with H and E staining, and the gene and protein expressions were determined by RT-PCR and Western blotting, respectively. PLCSB (20 µg·mL(-1)) could increase the growth of BRL 3A rat liver cells treated with CCl4. The serum levels of AST, ALT, and LDH were significantly decreased when the mice were treated with two doses of PLCSB, compared with the control mice (P < 0.05). PLCSB-treated groups also showed reduced levels of the serum pro-inflammatory cytokines IL-6, IL-12, TNF-α, and IFN-γ. PLCSB could decrease the liver weight, compared to the CCl4-treated control mice. The histopathology sections of liver tissues in the 100 mg·kg(-1) PLCSB group indicated that the animals were recovered well from CCl4 damage, but the 50 mg·kg(-1) PLCSB group showed necrosis to a more serious extent. The 100 mg·kg(-1) PLCSB group showed significantly decreased mRNA and protein expression levels of NF-κB, iNOS, and COX-2, and increased expression of IκB-α compared with the CCl4-treated control group. In conclusion, PLCSB prevented from CCl4-induced hepatic damage in vivo.

A pre-clinical pharmacokinetic study in rats of three naturally occurring iridoid glycosides, Picroside-I, II and III, using a validated simultaneous HPLC-MS/MS assay.

A selective and sensitive high-performance liquid chromatography-electro-spray ionization tandem mass spectrometry (LC-ESI-MS/MS) method was developed for the simultaneous quantitative determination of Picroside-I, II, and III in rat plasma and tissue homogenate to aid the pre-clinical studies. The chromatographic separation was performed on a Hypersil GOLD AQ C18 column using a gradient elution program with a mobile phase consisting of 2mM ammonium acetate and acetonitrile. The detection was achieved using a triple quadrupole tandem MS in negative ionization multiple reaction monitoring (MRM) mode. One-step protein precipitation was selected for plasma and tissue sample preparation while liquid-liquid extraction failed to achieve satisfactory recoveries. The calibration curves of all three analytes in either plasma or tissue homogenate showed good linearity over the concentration range of 0.5-500ng/mL with a limit of quantitation at 0.5ng/mL. Both the intra- and inter-day accuracy and precision were within ±10%. The extraction recoveries were >70%, and the relative matrix effect ranged from 80.4% to 107.4% in all the biological samples. All the analytes were stable in matrices for at least 24h at room temperature, or 21 days in frozen. Three freeze/thaw cycles did not cause degradation. The method was successfully applied for quantification of the three iridoid glycosides in the collected plasma and various tissues following intravenous administration in rats. Picroside-I, II, and III were all eliminated rapidly with large volume of distribution. Among the three glycosides, Picroside-II showed the highest liver uptake, and only Picroside-I and II were found to get across the blood brain barrier (BBB). These results were consistent with their hepatoprotective or neuroprotective effects reported clinically. With the aid of the efficient and reliable simultaneous LC-ESI-MS/MS assay this pharmacokinetic study provided insights into their therapeutic targets of these three iridoid glycosides as well as valuable experimental basis for an expansion of their clinical indications.

Bioaccessibility versus bioavailability of essential (Cu, Fe, Mn, and Zn) and toxic (Pb) elements from phyto hyperaccumulator Pistia stratiotes: potential risk of dietary intake.

Aquatic weeds are widely used as animal feed in developing countries. However, information about element bioavailability from these plants is lacking. A combination of an in vitro method [physiologically based extraction test (PBET)] and an in vivo feeding trial was used in this study to investigate potential element bioaccessibility and estimated bioavailability of Pistia stratiotes (PS). Cu, Fe, Mn, Zn, and Pb concentrations in PS biomass, artificial gastrointestinal fluids, and rat tissues were determined using atomic absorption spectrometry with electrothermal atomization and inductively coupled plasma-atomic emission spectrometry. PS exhibited elevated Fe, Mn, and Pb levels. The PBET revealed high bioaccessibility of all monitored elements from PS biomass. The results of the in vivo trial were inconsistent with those of the PBET, because animals fed PS exhibited low levels of essential elements in the tissues. The consumption of a PS-supplemented diet significantly decreased total Fe levels and increased the total level of accumulation of Pb in exposed animals. Significantly reduced amounts of essential elements in the intestinal walls indicated a potential disruption in nutrient gastrointestinal absorption in animals fed PS.

Molecular characterisation of the salmon louse, Lepeophtheirus salmonis salmonis (Krøyer, 1837), ecdysone receptor with emphasis on functional studies of female reproduction.

The salmon louse Lepeophtheirus salmonis (Copepoda, Caligidae) is an important parasite in the salmon farming industry in the Northern Hemisphere causing annual losses of hundreds of millions of dollars (US) worldwide. To facilitate development of a vaccine or other novel measures to gain control of the parasite, knowledge about molecular biological functions of L. salmonis is vital. In arthropods, a nuclear receptor complex consisting of the ecdysone receptor and the retinoid X receptor, ultraspiracle, are well known to be involved in a variety of both developmental and reproductive processes. To investigate the role of the ecdysone receptor in the salmon louse, we isolated and characterised cDNA with the 5'untranslated region of the predicted L. salmonis EcR (LsEcR). The LsEcR cDNA was 1608 bp encoding a 536 amino acid sequence that demonstrated high sequence similarities to other arthropod ecdysone receptors including Tribolium castaneum and Locusta migratoria. Moreover, in situ analysis of adult female lice revealed that the LsEcR transcript is localised in a wide variety of tissues such as ovaries, sub-cuticula and oocytes. Knock-down studies of LsEcR using RNA interference terminated egg production, indicating that the LsEcR plays important roles in reproduction and oocyte maturation. We believe this is the first report on the ecdysone receptor in the economically important parasite L. salmonis.

Tracing Mercox Injected at Acupuncture Points Under the Protocol of Partial Body Macerations in Mice.

We used for the first time a vascular casting material to take advantage of a simple tracing procedure and to isolate the peculiar features of acupuncture point injections. The polymer Mercox was injected into the skin of a dead mouse at acupuncture points along the bladder meridian lines. After a partial maceration of the whole body with a potassium-hydroperoxide solution, we anatomized it under a stereomicroscope to trace the injected Mercox. Many organs were checked to determine whether or not they contained some Mercox tracing. Connections between the injection sites along the acupuncture points were observed. Two to three layers of Mercox in a plate shape were found under the skin at the acupuncture points, and Mercox travelled throughout the adipose tissue, the fascia, and the parietal and visceral serous membranes inside the organ's parenchyma. The casting material Mercox used with a modified partial maceration procedure is a promising method for visualizing the routes of the meridian system and the primo vascular system. The routes for Mercox are different from those of the blood and lymphatic vessels.

Mass spectrometric evaluation of neuropeptidomic profiles upon heat stabilization treatment of neuroendocrine tissues in crustaceans.

Tissue heat stabilization is a vital component in successful mammalian neuropeptidomic studies. Heat stabilization using focused microwave irradiation, conventional microwave irradiation, boiling, and treatment with the Denator Stabilizor T1 have all proven effective in arresting post-mortem protein degradation. Although research has reported the presence of protein fragments in crustacean hemolymph when protease inhibitors were not added to the sample, the degree to which post-mortem protease activity affects neuropeptidomic tissue studies in crustacean species has not been investigated in depth. This work examines the need for Stabilizor T1 or boiling tissue stabilization methods for neuropeptide studies of Callinectes sapidus (blue crab) pericardial organ tissue. Neuropeptides in stabilized and nonstabilized tissue were extracted using acidified methanol or N,N-dimethylformamide (DMF) and analyzed by MALDI-TOF and nanoLC-ESI-MS/MS platforms. Post-mortem fragments did not dramatically affect MALDI analysis in the range m/z 650-1600, but observations in ESI MS/MS experiments suggest that putative post-mortem fragments can mask neuropeptide signal and add spectral complexity to crustacean neuropeptidomic studies. The impact of the added spectral complexity did not dramatically affect the number of detected neuropeptides between stabilized and nonstabilized tissues. However, it is prudent that neuropeptidomic studies of crustacean species include a preliminary experiment using the heat stabilization method to assess the extent of neuropeptide masking by larger, highly charged molecular species.

The stomatopod dactyl club: a formidable damage-tolerant biological hammer.

Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance. One such example is found in the hypermineralized hammer-like dactyl clubs of the stomatopods, a group of highly aggressive marine crustaceans. The dactyl clubs from one species, Odontodactylus scyllarus, exhibit an impressive set of characteristics adapted for surviving high-velocity impacts on the heavily mineralized prey on which they feed. Consisting of a multiphase composite of oriented crystalline hydroxyapatite and amorphous calcium phosphate and carbonate, in conjunction with a highly expanded helicoidal organization of the fibrillar chitinous organic matrix, these structures display several effective lines of defense against catastrophic failure during repetitive high-energy loading events.

[Allometry of scales in Chinese pangolins (Manis pentadactyla) and Malayan pangolins (Manis javanica) and application in judicial expertise].

Pangolins are unique mammals in that they possess scales that serve a protective biological function. As an important raw material of traditional medicine, illegal trades of these scales are frequent and difficult to investigate or prosecute. We used allometric models of dry weight of scales to compare 35 Chinese pangolins (Manis pentadactyla) and 119 Malayan pangolins (Manis javanica). Our results showed that the dry weight of scales increases significantly faster with the length of head and body in Malayan pangolins (P=0.005), while dry weight of scales is positive (slope=3.725) in Malayan pangolins but isometric (slope=3.105) in Chinese pangolins. The differences in morphology between these species may reflect an evolutionary adaptation to different environments; Malayan pangolins in tropical regions appear to suffer from greater predation pressure than Chinese pangolins in temperate regions. We advise the conversion standards between dry weight of scales and number of individuals as 573.47 g in Chinese pangolins and 360.51 g in Malayan pangolins respectively, and when two are mixed together, average above two parameters of the median at 466.99 g. We propose these measurements be used as judicial evidences in forensic identification of related cases.

Pharmacokinetics, tissue distribution and immunomodulatory effect of intralipid formulation of nystatin in mice.

OBJECTIVES: We developed a novel lipid formulation of nystatin suitable for parenteral administration, nystatin-intralipid (NYT-IL), with antifungal activity and reduced toxicity in mice. We investigated the pharmacokinetics, tissue distribution and immunomodulatory effect of NYT-IL in mice. METHODS: Nystatin levels in serum and organs were determined using HPLC after NYT-IL or nystatin administration in mice. The levels of the pro-inflammatory cytokines tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) and the anti-inflammatory cytokine interleukin 10 (IL-10) produced by splenocytes from mice injected with NYT-IL or nystatin were evaluated by an ELISA assay. RESULTS: Injection of NYT-IL resulted in similar levels and similar kinetics of nystatin in serum, higher concentrations in the liver and lower concentrations in the kidneys, in comparison with nystatin injection. Injection of mice with NYT-IL yielded higher levels of IL-10 than that of nystatin, whereas the levels of TNF-α and IFN-γ induced by NYT-IL were lower than those elicited by nystatin. CONCLUSIONS: Since polyene treatment is associated with nephrotoxicity, lower levels of nystatin in the kidneys following NYT-IL injection suggest the possibility of reduced toxicity. As the acute infusion-related adverse effects associated with polyene treatment are considered to be induced by pro-inflammatory cytokines, a higher level of anti-inflammatory and lower levels of pro-inflammatory cytokines elicited by NYT-IL administration suggest the possibility of amelioration of such effects. In summary, the altered pharmacokinetics, tissue distribution and immune response due to the use of this intralipid formulation of nystatin merit further research towards the development of a therapeutic agent against invasive mycoses.

Molecular diversity of the telson and venom components from Pandinus cavimanus (Scorpionidae Latreille 1802): transcriptome, venomics and function.

Venom from the scorpion Pandinus cavimanus was obtained by electrical stimulation of the telson (stinger). Total venom was toxic to crickets at 7-30 µg and a paralysis or lethal effect was observed at 30 µg of venom (death at 1.5 µg/mg of cricket). Electrophysiological analyses showed cytolytic activity of total venom on oocytes at 7 µg. HPLC allowed separation of the venom components. A total of 38 fractions from total venom were tested on voltage-gated Na(+) and K(+) channels. Some fractions block K(+) currents in different degrees. By using MS analysis, we obtained more than 700 different molecular masses from telson and venom fractions (by LC-MS/MS and MALDI-TOF MS analyses). The number of disulfide bridges of the telson components was determined. A cDNA library from P. cavimanus scorpion was constructed and a random sequencing screening of transcripts was conducted. Different clones were obtained and were analyzed by bioinformatics tools. Our results reveal information about new genes related to some cellular processes and genes involved in venom gland functions (toxins, phospholipases and antimicrobial peptides). Expressed sequence tags from venom glands provide complementary information to MS and reveal undescribed components related to the biological activity of the venom.

Viability assessment of primo-node slices from organ surface primo-vascular tissues in rats.

The primo-vascular system is a novel thread-like structure which is recently rediscovered, but its cellular properties are largely unknown. In this study, a slice preparation for primo-nodes was developed to facilitate study of the cellular properties of primo-node cells in vitro. Slices (4-8 slices; 200 µm thick) were sectioned from single primo-nodes collected from the abdominal organ surface of rats and incubated in oxygenated Krebs solution at 25°C or 31°C for up to 7 hours. Trypan blue staining and whole-cell patch-clamp recordings were performed to estimate the viability of cells in the slices. Viability was largely maintained during the first 3 hours, but subsequently decreased (from 80% to 21%, p < 0.001). In addition, the viability of slices incubated at 31°C was higher than those incubated at 25°C (80%vs. 47%, p < 0.001). In whole-cell patch-clamp experiments, high resistance seals readily formed and primo-node cells showed a mean resting membrane potential (-38 mV) comparable to that recorded with sharp electrodes and outwardly-rectifying current-voltage relationships. The results show that the primo-node slices developed in this study maintained viability for up to 4 hours in vitro.

Short chain saturated fatty acids decrease circulating cholesterol and increase tissue PUFA content in the rat.

This study investigates the effect of various dietary saturated fatty acid (SFA) profiles on plasma lipid parameters and tissue fatty acid composition in rats. The experiment was designed to monitor polyunsaturated fatty acids (PUFA) levels, while examining different amounts and types of SFA. Four isocaloric diets were prepared, containing 10-11 mol% of fatty acids (FA) as linoleic acid (LNA) and 2.5 mol% as α-linolenic acid (ALA), leading to an identical and well-balanced LNA/ALA ratio. The initial rapeseed oil/corn oil mixture providing ALA and LNA was enriched with olive oil to prepare the olive oil diet. The butterfat diet was supplemented with butterfat, containing short-chain SFA (C4:0-C10:0, 17 mol% of FA), lauric acid (C12:0, 3.2 mol%), myristic acid (C14:0, 10.5 mol%) and palmitic acid (C16:0, 14.5 mol%). The saturates diet was supplemented with trilaurin, trimyristin and tripalmitin to obtain the same level of lauric, myristic and palmitic acids as the butterfat diet, without the short-chain SFA. The trimyristin diet was enriched with trimyristin only. The results showed that the butterfat diet contributed to specific effects, compared to the olive oil diet and the saturates and trimyristin diets: a decrease in plasma total, LDL- and HDL-cholesterol, higher tissue storage of ALA and LNA, and a higher level of (n-3) highly unsaturated fatty acids in some tissues. This study supports the hypothesis that in diets with identical well-balanced LNA/ALA ratios, short chain SFA may decrease circulating cholesterol and increase tissue polyunsaturated fatty acid content in the rat.

Impact of chemical manipulation of tarsal liquids on attachment in the Colorado potato beetle, Leptinotarsa decemlineata.

Insect tarsal attachment forces are thought to be influenced by the viscosity and surface tension of a thin film of adhesive liquid (wet adhesion). In beetles, this fluid has been shown to be composed mainly of lipophilic substances that are similar to the cuticular lipids. In this study we investigate whether and how the chemical composition of footprint lipids affects attachment forces in the Colorado potato beetle, Leptinotarsa decemlineata. After application of standardised mixtures of synthetic n-alkanes or alkenes, or a concentrated hydrocarbon extract to the surface of the elytra, we tested the beetles' attachment performance using a beam force transducer. The results show that only the unsaturated components, but not the straight-chained alkanes reduced friction forces, confirming that attachment performance is influenced by the chemical composition of the adhesive secretion. We estimated the volume of footprint droplets and calculated a mean thickness of the liquid layer of 0.04 microm. The measured friction exceeded the viscous and capillary force expected for a film of this thickness. Therefore, alternative mechanisms (i.e. shear-thinning and solid-like behaviour) for the generation of attachment forces and their dependence on the chemical composition of the liquid are discussed.

Mass spectrometric characterization and physiological actions of novel crustacean C-type allatostatins.

The crustacean stomatogastric ganglion (STG) is modulated by numerous neuropeptides that are released locally in the neuropil or that reach the STG as neurohormones. Using 1,5-diaminonaphthalene (DAN) as a reductive screening matrix for matrix-assisted laser desorption/ionization (MALDI) mass spectrometric profiling of disulfide bond-containing C-type allatostatin peptides followed by electrospray ionization quadrupole time-of-flight (ESI-Q-TOF) tandem mass spectrometric (MS/MS) analysis, we identified and sequenced a novel C-type allatostatin peptide (CbAST-C1), pQIRYHQCYFNPISCF-COOH, present in the pericardial organs of the crab, Cancer borealis. Another C-type allatostatin (CbAST-C2), SYWKQCAFNAVSCFamide, was discovered using the expressed sequence tag (EST) database search strategy in both C. borealis and the lobster, Homarus americanus, and further confirmed with de novo sequencing using ESI-Q-TOF tandem MS. Electrophysiological experiments demonstrated that both CbAST-C1 and CbAST-C2 inhibited the frequency of the pyloric rhythm of the STG, in a state-dependent manner. At 10(-6)M, both peptides were only modestly effective when initial frequencies of the pyloric rhythm were >0.8Hz, but almost completely suppressed the pyloric rhythm when applied to preparations with starting frequencies <0.7Hz. Surprisingly, these state-dependent actions are similar to those of the structurally unrelated allatostatin A and allatostatin B families of peptides.

Characterisation of the carotenoprotein found in carapace shells of Jasus lalandii.

Carotenoprotein, containing astaxanthin as the prosthetic group was extracted from the carapace shells of the lobster, Jasus lalandii. The material, with a molecular mass of around 400,000 Da and lambda(max) 525 nm (alpha-crustacyanin), was readily converted under the conditions used for extraction and on standing to the subunit (beta-crustacyanin) of molecular mass around 40,000 Da and lambda(max) 560 nm. The latter complex was stable up to 65 degrees C and between pH 5 and 8. Both the large molecule and the subunit showed the reversible bathochromic shift (lambda(max) approximately 480 nm) after being subjected to conditions of heat above 65 degrees C and below 85 degrees C and pH between 3 and 10, which alter the natural protein orientation. Above 85 degrees C and outside of the pH range, the shift was irreversible. Crustacyanin from J. lalandii differed from the blue crustacyanin of the Homarus species with respect to visible spectra (lambda(max) 632 nm and lambda(max) 585 nm) and by displaying a hypsochromic shift between the alpha- and beta-crustacyanin. Stability of the alpha-crustacyanin and affinity to DE52 also differed. Yellow protein, with a lambda(max) 409/410 nm as described for the Homarus species was not detected in this J. lalandii study, although it may have been co-eluted. The properties of the extracted complex show potential for its use as a natural water soluble food colourant or temperature sensitive indicator.

Comparison of the characteristic features of Bonghan ducts, blood and lymphatic capillaries.

OBJECTIVE: To show that the characteristic morphological and ultrastructural features of a Bonghan corpuscle and duct presented here are consistent with the description given in the early reports of Bonghan Kim. MATERIALS AND METHODS: We compared the morphological aspects of Bonghan ducts with those of blood and lymphatic capillaries on the ultrastructural level to display the manifestly distinctive nature of the Bonghan system. RESULTS: The walls of the ductules were observed to be composed of a single layer of endothelial cells with characteristic rod-shaped nuclei and were not surrounded by a basal lamina or by accessory cells, such as pericytes or smooth muscle cells. The abluminal cell membranes of Bonghan ductules were not attached by anchoring filaments to the fibers of extracellular matrices as observed in lymphatic capillaries. The cytoplasmic processes of ductule endothelial cells appear to form overlapping and interdigitated interconnections which completely lack junctional elements. Although the cytoplasm of ductule endothelial cells contained a well-developed rough endoplasmic reticulum and many free ribosomes and polysomes, there was a relatively small number of pinocytotic vesicles and lacks specific organelles, such as Weibel-Palade bodies. CONCLUSIONS: The Bonghan corpuscles are specialized structures consisting of different types of immune cells randomly scattered as single cells in the matrix or clustered in follicle-like formations. Moreover, the Bonghan ductules in the corpuscle contain flowing immune cells and occasionally basophilic bodies.

Exploring gradients of halogens and zinc in the surface and subsurface of Nereis jaws.

The outstanding mechanical properties of impact-bearing tissues, such as Nereis jaws, make their morphology and chemical composition a subject of particular interest. The complex structure of the jaw was recently reported to exhibit molecular gradients that were closely correlated with stiffness and hardness.(18) Accordingly, we have explored the spatial distribution and bonding chemistries of Zn and the halogens in the surface structure of the jaws. Using secondary ion mass spectrometry (SIMS) and scanning electron microscopy (SEM), we found that Cl, Br, and I distributions are enhanced in surface layers of the basal protected portion of the jaw but are shifted to greater depths toward the exposed jaw tip. There are thus two complementary halogen gradients in the jaw: one on the surface that decreases from the base to the tip, coupled to an increasing one in the subsurface layers. The outer surface coating appeared to have granular morphology, in contrast to the anisotropic, fibrous core that dominates the subarchitecture. Using X-ray photoelectron spectroscopy (XPS), we discovered that Zn, I, and Br in the jaws have single chemical environments whereas chlorine is present in two distinct modes (Cl-Zn and Cl-C). Given the inverse relationship between surface exposure and halogen abundance in the jaws, it is unlikely that the halogens contribute directly to mechanical properties such as wear and hardness.