Concentric Lamellar Structures Research Articles

Strategic band alignment of zinc oxide photoanode with fibrous silica framework for enhanced photoelectrochemical water splitting efficiency

The urgent need to address both energy demand and environmental concerns has led to the exploration of solar energy utilization in photoelectrochemical (PEC) water splitting. The novelty of fibrous silica zinc oxide photoanode (FSZn) was introduced in this groundbreaking study, synthesized using the meticulous microemulsion method. Our investigation reveals the exceptional properties of FSZn using a comprehensive range of analytical techniques, including FESEM, FTIR, XRD, UV–Vis/DRS TEM, and N2 adsorption–desorption tests. The distinctive features of FSZn arise from its intricate bicontinuous concentric lamellar structure, resulting in a narrow bandgap and a vast surface area. Notably, FSZn exhibits a remarkable photocurrent density of 17.88 mA/cm2, surpassing that of conventional ZnO, which only yields 6.28 mA/cm2. Furthermore, FSZn achieves an impressive solar-to-hydrogen (STH) efficiency of 22.0 %. The favourable alignment of FSZn’s conduction band with the hydrogen reduction potential, which facilitates swift and efficient charge transfer processes conducive to spontaneous hydrogen generation, is responsible for this remarkable performance. The successful development of FSZn represents a significant milestone, offering valuable insights for advancing high-performance photoanodes. By significantly enhancing the efficiency of photoanodes in PEC water splitting processes, FSZn holds promise for accelerating the transition towards sustainable energy solutions.

Liesegang rings in kidney diseases- A Systematic Review.

Liesegang rings (LR) are concentric acellular lamellar structures, usually found in cystic and inflammatory tissues but can also be seen in neoplastic conditions. They have been mistakenly interpreted as various structures like psammomatous calcification, parasites, and algae. This study has aimed to systematically review and summarize the existence of LRs in both non-neoplastic and neoplastic conditions of the kidney. The systematic search in PUBMED, PUBMED CENTRAL, and EMBASE databases along with Google Scholar was performed by using Kidney, Liesegang Rings, or Liesegang structure or pseudo parasitic structure in combination with the Boolean operators ''and'' as searching terms. Data were collected for demographic characteristics and histopathology diagnosis. The search function was limited to human subjects. Two reviewers independently performed the eligibility assessment and data extraction. Eligibility inclusion criteria were all publications in the English literature worldwide related to Liesegang rings in association with kidney's non-neoplastic and neoplastic conditions, regardless of the years of publication. Also included were those cases whose full articles were unavailable, but the abstract was well-described, fulfilling our inclusive criteria. Eligibility exclusion criteria included LRs found elsewhere in the body organs apart from the kidney and availability of full text in a different language, non-human, and duplicate article/case. After the exclusion of the articles as per the exclusion criteria, the total articles that fulfilled the inclusive criteria were reviewed. In addition, all the articles were further cross-referenced for additional articles. All published papers retrieved from this search were considered for this review. A total of 22 records (26 cases) were found with a diagnosis of LRs in the kidney to date. Some articles were published as case series. Accordingly, 26 patients were reported to have Liesegang rings associated with kidney neoplastic and non-neoplastic conditions, 12 were male and 14 were female. For one case the gender was not mentioned. LRs presented a higher frequency in individuals between the 4th and 5th decades of life. No single case was reported in infants and younger children. Regarding predisposing factors for LRs, cystic fluid contents were the most common underlying condition. In our practice, we encountered an unusual case of a 55-year-old female with a complaint of pain in the left upper quadrant of the abdomen. The ultrasound revealed nephrolithiasis and chronic kidney disease for which a nephrectomy was performed. On the histopathological examination, there was an incidental finding of Liesegang rings and a papillary adenoma along with features of chronic pyelonephritis. Our review will provide insight into LRs in different spectrums of kidney diseases. This study represents the first available systematic review of the literature demonstrating LRs in the kidney. Although Liesegang rings have no great clinical significance, nonetheless, their presence in both tissue and cytological specimens should be kept in mind while dealing with different lesions of the kidney as they are good mimickers of many organic and inorganic substances, parasites, and malignancies.

Biomimetic Nacre-like Hydroxyapatite/Polymer Composites for Bone Implants.

One of the most ambitious goals for bone implants is to improve bioactivity, incapability, and mechanical properties; to reduce the need for further surgery; and increase efficiency. Hydroxyapatite (HA), the main inorganic component of bones and teeth, has high biocompatibility but is weak and brittle material. Cortical bone is composed of 70% calcium phosphate (CaP) and 30% collagen and forms a complex hierarchical structure with anisotropic and lamellar microstructure (osteons) which makes bone a light, strong, tough, and durable material that can support large loads. However, imitation of concentric lamellar structure of osteons is difficult to achieve in fabrication. Nacre from mollusk shells with layered structures has now become the archetype of the natural "model" for bio-inspired materials. Incorporating a nacre-like layered structure into bone implants can enhance their mechanical strength, toughness, and durability, reducing the risk of implant catastrophic failure or fracture. The layered structure of nacre-like HA/polymer composites possess high strength, toughness, and tunable stiffness which matches that of bone. The nacre-like HA/polymer composites should also possess excellent biocompatibility and bioactivity which facilitate the bonding of the implant with the surrounding bone, leading to improved implant stability and long-term success. To achieve this, a bi-directional freeze-casting technique was used to produce elongated lamellar HA were further densified and infiltrated with polymer to produce nacre-like HA/polymer composites with high strength and fracture toughness. Mechanical characterization shows that increasing the ceramic fractions in the composite increases the density of the mineral bridges, resulting in higher flexural and compressive strength. The nacre-like HA/(methyl methacrylate (MMA) + 5 wt.% acrylic acid (AA)) composites with a ceramic fraction of 80 vol.% showed a flexural strength of 158 ± 7.02 MPa and a Young's modulus of 24 ± 4.34 GPa, compared with 130 ± 5.82 MPa and 19.75 ± 2.38 GPa, in the composite of HA/PMMA, due to the higher strength of the polymer and the interface of the composite. The fracture toughness in the composition of 5 wt.% PAA to PMMA improves from 3.023 ± 0.98 MPa·m1/2 to 5.27 ± 1.033 MPa·m1/2 by increasing the ceramic fraction from 70 vol.% to 80 vol.%, respectively.

Research on biomimetic design and impact characteristics of periodic multilayer helical structures.

Osteons are composed of concentric lamellar structure, the concentric lamellae are composed of periodic thin and thick sub-lamellae, and every 5 sub-lamellae is a cycle, the periodic helix angle of mineralized collagen fibers in two adjacent sub-lamellae is 30°. Four biomimetic models with different fiber helix angles were established and fabricated according to the micro-nano structure of osteon. The effects of the fiber periodic helical structure on impact characteristic and energy dissipation of multi-layer biomimetic composite were investigated. The calculation results indicated that the stress distribution, contact characteristics and fiber failur during impact, and energy dissipation of the composite are affected by the fiber helix angle. The stress concentration of composite materials under external impact can be effectively improved by adjusting the fiber helix angle when the material composition and material performance parameters are same. Compared with the sample30, the maximum stress of sample60 and sample90 increases by 38.1% and 69.8%, respectively. And the fiber failure analysis results shown that the model with a fiber helix angle of 30° has a better resist impact damage. The drop-weight test results shown that the impact damage area of the specimen with 30° helix angle is smallest among the four types of biomimetic specimens. The periodic helical structure of mineralized collagen fibers in osteon can effectively improve the impact resistance of cortical bone. The research results can provide useful guidance for the design and manufacture of high-performance, impact-resistant biomimetic composite materials.

Si-Ti interaction in unique morphology of fibrous silica titania photoanode for enhanced photoelectrochemical water splitting

Extensive efforts toward titania (TiO2) modification have been developed in order to overcome the shortcomings as an efficient photoanode for photoelectrochemical (PEC) water splitting. Herein, a unique morphology possessed fibrous silica titania (FST) fabricated by microemulsion method was used for the first time as a photoanode. The FST was characterized by XRD, Raman, N2 adsorption–desorption, FESEM, TEM, FTIR, XPS, UV–vis/DRS, and PL. The results confirmed the creation of a bicontinuous concentric lamellar structure of FST with a high surface area. The inclusions of Ti in the silica matrix induced the Si-Ti interaction and narrowed the band gap. The FST photoanode exhibited a superior photocurrent density of 13.79 mA/cm2 with 16.9 % solar-to-hydrogen (STH) efficiency, which is 2.5 times higher compared to commercial TiO2 which performed at 5.51 mA/cm2 with 6.8 % STH. Significantly, the conduction band of FST lies closer to the reduction potential of hydrogen compared to TiO2, leading to the fast charge transfer and allowing spontaneous production of H2. The fabrication of FST provided new insight into developing high-performance photoanode for enhanced PEC water splitting.

Rapid Responsive Mechanochromic Photonic Pigments with Alternating Glassy-Rubbery Concentric Lamellar Nanostructures.

Photonic pigment particles prepared via self-assembly have been suffering from their poor mechanical performances; i.e., they can easily be damaged and lose structural color under a compression force. This greatly limits their uses as mechanochromic pigments. Here, a nanoscale concentric lamellar structure of alternating glassy-rubbery microdomains is successfully created within photonic microparticles through a confined self-assembly and photo-cross-linking strategy. The glassy domain is composed of polystyrene, and cross-linked bottlebrush polydimethylsiloxane served as the supersoft elastic domain. The obtained photonic structure not only shows large deformation and visible color changes under a loaded compression force but also rapidly recovers to its original state in less than 1 s (∼0.16 s) upon unloading. Continuously loading-unloading micro compression test indicates that no obvious damage can be identified after 250 cycles, indicating the high durability of the pigments against deformation. These pigments with different reflected colors are simply obtained using bottlebrush block copolymer formulations with tunable weight percentages of polymer additives. The mechanical robust photonic pigments may be useful in many important applications.

Ultrafine-grained graphite prepared from filler of onion-like carbon spheres via a liquid mixing process for using in molten salt reactor

Ultrafine-grained graphite (UG) has been prepared via a liquid mixing process using onion-like carbon spheres (OLC) as filler for comparison to a control sample with calcined pitch cokes (PC) as filler. The same coal-tar pitch was used for both. The average particle sizes of both OLC and PC were 7 μm. The graphite derived from filler of OLC exhibited superior properties of higher mechanical strength, more compact structures, higher isotropy and much better barrier property to molten salt than the graphite derived from filler of PC. This suggests that OLC has some advantages over PC as the filler for the preparation of nuclear graphite for using in molten salt reactor. The relevant mechanisms are analyzed and discussed in detail based on the structure and property advantages of OLC over PC such as more compact structure, special concentric lamellar structure and 6 wt% of volatile. Moreover, in terms of UG prepared from filler of OLC, the following issues are required to investigate in the future such as improving its thermal conductivity, reducing its coefficient of thermal expansion and elucidating its irradiation behaviors.

Role of oxygen vacancies in dendritic fibrous M/KCC-1 (M = Ru, Pd, Rh) catalysts for methane partial oxidation to H2-rich syngas production

The fibrous M/KCC-1 (M = Ru, Pd, Rh) catalysts prepared by microwave-assisted hydrothermal approach were investigated for methane partial oxidation (MPO) reaction at stoichiometric CH4/O2 feed ratio and temperature of 500–800 °C. A drop in BET surface area with metal oxide addition suggesting the successful embedment of metal oxides on KCC-1. Low-angle XRD, FTIR and TEM analyses confirmed the formation of bicontinuous concentric lamellar morphologic structure, typical fingerprint of fibrous KCC-1. The H2-TPR and ESR studies revealed that oxygen vacancy (OV) of KCC-1 not only beneficial for the metal-support interactions of catalysts but also strongly and dissociately bind with O2, CO2 and H2O promoting the syngas formation rate. The post-reaction Raman spectroscopy measurement corroborated the M/KCC-1 catalysts hindered the graphitic carbon formation during reaction. The Rh/KCC-1 appeared to be the optimum catalyst as it exhibited the TOF of both CH4 consumption and H2 formation about 2-fold higher to other catalysts meanwhile achieving H2/CO ratio about 2.16 that applicable for industrial applications. Based on the experimental MPO evaluation, post-reaction Raman spectroscopy and the in-situ ESR studies, the synergistic effects of metals and OV from fibrous KCC-1, where metal dissociates CH bonds in CH4 molecules whilst OV generates activated O2− species from oxidants at the OV sites, are determined as the key factors for the enhancement in MPO activity.

Phase behavior of disk-coil block copolymers under cylindrical confinement: Curvature-induced structural frustrations.

In this paper, we explore the self-assembly behavior of disk-coil block copolymers (BCPs) confined within a cylinder using molecular dynamics simulations. As functions of the diameter of the confining cylinder and the number of coil beads, concentric lamellar structures are obtained with a different number of alternating disk-rich and coil-rich bilayers. Our paper focuses on the curvature-induced structural behavior in the disk-rich domain of a self-assembled structure, which is investigated by calculating the local density distribution P(r) and the orientational distribution G(r,θ). In the inner layers of cylinder-confined disk-coil BCPs, both P(r) and G(r,θ) show characteristic asymmetry within a bilayer which is directly contrasted with the bulk and slab-confined disk-coil BCPs. We successfully explain the structural frustration of disks arising from the curved structure due to packing frustration of disks and asymmetric stretching of coils to the regions with different curvatures in a bilayer. Our results are important to understand the self-assembly behavior of BCPs containing a rigid motif in a confined structure, such as a self-assembled structure of bacteriochlorophyll molecules confined by a lipid layer to form a chlorosome, the photosynthetic antennae complex found in nature.

Additional Lewis acid sites of protonated fibrous silica@BEA zeolite (HSi@BEA) improving the generation of protonic acid sites in the isomerization of C6 alkane and cycloalkanes

This paper describes a study of the nature of metal-free protonated fibrous silica BEA (HSi@BEA) and its ability to generate protonic acid sites originating from molecular hydrogen and from C6 alkanes and cycloalkanes. HSi@BEA was successfully synthesized by a microemulsion system and subsequently applied in n-hexane, cyclohexane and methylcyclopentane isomerization. The HSi@BEA consisted of microspheres with a bicontinuous concentric lamellar structure morphology. Its core was mainly composed of an aluminosilicate framework of BEA, while the lamellar structure consisted of silica. The particle size of HSi@BEA was in the range of 400 nm to 700 nm with pore diameters between 3.6 nm to 5.6 nm and 15 nm to 25 nm. 27 Al MAS NMR results showed that the additional silica lamellar structure of the HSi@BEA increased the extra-framework aluminum (AlOH) which acts as Lewis acidic sites in the catalyst. FTIR results revealed that these additional Lewis acid sites in the metal-free catalyst generated a high amount of protonic acid sites by playing a role as electron acceptors after the dissociation of H2 and C6 alkane and cycloalkanes. Significantly, the participation of more protonic acid sites enhanced the catalytic performance of the C6 alkanes and cycloalkanes, n-hexane, cyclohexane and methylcyclopentane, at a low reaction temperature of 423 K. The presence of a silica lamellar structure resulted in a two to threefold higher isomer yield of n-hexane, cyclohexane and methylcyclopentane compared to bare HBEA catalyst which mainly produces cracking products. In addition, a kinetics study showed that the activation energy could be lowered by two to three times at elevated temperatures in the range of 423 K to 623 K.

Responsive Block Copolymer Photonic Microspheres.

Responsive photonic crystals (PCs) have attracted much attention due to their broad applications in the field of chemical and physical sensing through varying optical properties when exposed to external stimuli. In particular, assembly of block copolymers (BCPs) has proven to be a robust platform for constructing PCs in the form of films or bulk. Here, the generation of BCPs photonic microspheres is presented with 3D periodical concentric lamellar structures through confined self-assembly. The structural color of the spherical PCs can be tuned by selective swelling of one block, yielding large change of optical property through varying both layer thickness and refraction index of the domains. The as-formed spherical PCs demonstrate large reflection wavelength shift (≈400-700 nm) under organic solvent permeation and pH adjustment. Spherical shape and structural symmetry endow the formed spherical PCs with rotation independence and monochrome, which is potentially useful in the fields of displays, sensing, and diagnostics.

A morphological and biochemical evaluation of the effects of quercetin on experimental sciatic nerve damage in rats.

The present study evaluated the neuroprotective and antioxidant effects of quercetin in a rat model of sciatic nerve crush injury using histopathological, morphometric and biochemical methods. A total of 48 male Sprague Dawley rats, aged 10–12 weeks old were randomly divided into eight groups, consisting of two sham groups (S-7, S-28), three quercetin-treated groups (Q-7, Q-28; 200 mg/kg/7 days), trauma (T-7, T-28; 1 min sciatic nerve crush injury) and three trauma+quercetin groups (T+Q-7, T+Q-28; trauma+quercetin 200 mg/kg/7 days). Rats were sacrificed on day 7 or 28. Oxidant-antioxidant biochemical parameters in nerve tissues from all groups were analyzed using histopathological staining with toluidine blue and Masson's trichrome. DNA fragmentations were identified using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling in cells from each tissue sample. Degeneration of the axons and myelin sheath, the breakdown of the concentric lamellar structure of the myelin sheath and axonal swelling were observed in groups T-7 and T-28. Myelin sheath thicknesses, nerve fiber diameters and the number of myelinated nerve fibers decreased, while the apoptotic index (AI) increased in the T-7 and T-28 groups. However, it was observed that nerve regeneration began in the T+Q-7 and T+Q-28 groups compared with the sham groups, together with the healing of cellular damage and axonal structure and a decrease in the AI. Malondialdehyde and superoxide dismutase activity did not differ significantly between the T-7 and S-7 groups. However, catalase activity significantly decreased in the T-28 group when compared with the sham 7 day group. Tissue malondialdehyde levels significantly increased, while serum catalase activity increased in the T+Q-7 group compared with the T-7 group. These results suggest that quercetin has beneficial effects on nerve regeneration and may shorten the healing period in crush-type sciatic nerve injuries.

Histological and reference system for the analysis of mouse intervertebral disc.

A new scoring system based on histo-morphology of mouse intervertebral disc (IVD) was established to assess changes in different mouse models of IVD degeneration and repair. IVDs from mouse strains of different ages, transgenic mice, or models of artificially induced IVD degeneration were assessed. Morphological features consistently observed in normal, and early/later stages of degeneration were categorized into a scoring system focused on nucleus pulposus (NP) and annulus fibrosus (AF) changes. "Normal NP" exhibited a highly cellularized cell mass that decreased with natural ageing and in disc degeneration. "Normal AF" consisted of distinct concentric lamellar structures, which was disrupted in severe degeneration. NP/AF clefts indicated more severe changes. Consistent scores were obtained between experienced and new users. Altogether, our scoring system effectively differentiated IVD changes in various strains of wild-type and genetically modified mice and in induced models of IVD degeneration, and is applicable from the post-natal stage to the aged mouse. This scoring tool and reference resource addresses a pressing need in the field for studying IVD changes and cross-study comparisons in mice, and facilitates a means to normalize mouse IVD assessment between different laboratories. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:233-243, 2018.

The cement apparatus of the stalked barnacle Pollicipes pollicipes

Barnacles are sessile marine crustaceans that produce a proteinaceous cement to attach themselves to the underwater surfaces of natural or man-made structures. This work was carried out to characterize the cement apparatus and localize this structure in the peduncle of the stalked barnacle Pollicipes pollicipes. Light and transmission electron microscopy techniques were used for these purposes. Sections of the peduncle revealed a central core encircled by a thick layer of muscular tissue. The cement apparatus, formed by clusters of adhesive-secreting cells and ducts, was located in the central core embedded in an apical layer of connective tissue with a thickness of a few mm, just beneath the capitulum. The ovary was also found in the peduncular core, but most of it was located below the region containing the cement apparatus. The cytoplasm of adhesive-secreting cells was very rich in rough endoplasmic reticulum and also contained small electron-dense secretory vesicles. Histochemical methods applied to semithin sections showed that these vesicles were filled with proteins, being also PAS positive. The voluminous nuclei of these cells presented diverse and irregular shapes, typically with very thin and long extensions, containing large nucleoli and a great amount of heterochromatin. Electron-dense inclusions with a concentric lamellar structure were also seen in these nuclei, resembling nuclear inclusions reported in fish oocytes. These cells presented the features of very active protein-secreting cells, being similar to the adhesive-secreting cells of other species of stalked barnacles.

Tips and tricks for end-to-side anastomosis arteriotomies

Arteriotomy is a critical step during end-to-side anastomosis procedures. However, it is challenging to carry out because of the concentric lamellar structure of blood vessels and the need for clean margins. We performed a review of the literature to identify the advantages and disadvantages of the available arteriotomy methods. The techniques were classified into (1) single-cut or slit arteriotomy (longitudinal and transverse) or (2) excision arteriotomy. The latter techniques can be performed from either outside-in (excision with straight microscissors, curved microscissors, Acland-Banis arteriotomy clamp, micro-arteriotomy scissors, or triangular cutting scissors, and vaporization with Excimer® laser) or inside-out (excision with punch/micropunch). Microsurgeons have multiple arteriotomy methods at their disposal. By being familiar with these methods, they can select the most appropriate one for the situation at hand.

Structural Transformation of Diblock Copolymer/Homopolymer Assemblies by Tuning Cylindrical Confinement and Interfacial Interactions.

In this study, we report the controllable structural transformation of block copolymer/homopolymer binary blends in cylindrical nanopores. Polystyrene-b-poly(4-vinylpyridine)/homopolystyrene (SVP/hPS) nanorods (NRs) can be fabricated by pouring the polymers into an anodic aluminum oxide (AAO) channel and isolated by selective removal of the AAO membrane. In this two-dimensional (2D) confinement, SVP self-assembles into NRs with concentric lamellar structure, and the internal structure can be tailored with the addition of hPS. We show that the weight fraction and molecular weight of hPS and the diameter of the channels can significantly affect the internal structure of the NRs. Moreover, mesoporous materials with tunable pore shape, size, and packing style can be prepared by selective solvent swelling of the structured NRs. In addition, these NRs can transform into spherical structures through solvent-absorption annealing, triggering the conversion from 2D to 3D confinement. More importantly, the transformation dynamics can be tuned by varying the preference property of surfactant to the polymers. It is proven that the shape and internal structure of the polymer particles are dominated by the interfacial interactions governed by the surfactants.

Comparison of Decellularization Protocols for Preparing a Decellularized Porcine Annulus Fibrosus Scaffold

Tissue-specific extracellular matrix plays an important role in promoting tissue regeneration and repair. We hypothesized that decellularized annular fibrosus matrix may be an appropriate scaffold for annular fibrosus tissue engineering. We aimed to determine the optimal decellularization method suitable for annular fibrosus. Annular fibrosus tissue was treated with 3 different protocols with Triton X-100, sodium dodecyl sulfate (SDS) and trypsin. After the decellularization process, we examined cell removal and preservation of the matrix components, microstructure and mechanical function with the treatments to determine which method is more efficient. All 3 protocols achieved decellularization; however, SDS or trypsin disturbed the structure of the annular fibrosus. All protocols maintained collagen content, but glycosaminoglycan content was lost to different degrees, with the highest content with TritonX-100 treatment. Furthermore, SDS decreased the tensile mechanical property of annular fibrosus as compared with the other 2 protocols. MTT assay revealed that the decellularized annular fibrosus was not cytotoxic. Annular fibrosus cells seeded into the scaffold showed good viability. The Triton X-100–treated annular fibrosus retained major extracellular matrix components after thorough cell removal and preserved the concentric lamellar structure and tensile mechanical properties. As well, it possessed favorable biocompatibility, so it may be a suitable candidate as a scaffold for annular fibrosus tissue engineering.

Gross morphology and ultrastructure of salivary glands of the mute cicada Karenia caelatata Distant (Hemiptera: Cicadoidea)

Salivary glands of the cicada Karenia caelatata Distant were investigated using light microscopy and transmission electron microscopy. The salivary glands are paired structures and consist of principal glands and accessory glands. The principal gland is subdivided into anterior lobe and posterior lobe; the former contains about 34–39 long digitate lobules, while the latter contains approximately 30–33 long digitate lobules and 13–22 short digitate lobules. These short digitate lobules, about one fifth or sixth as long as the long digitate lobules, locate at the base of the long digitate lobules of posterior lobe. All of these digitate lobules vary in size, disposition, length and shape. The anterior lobe and the posterior lobe are connected by an anterior-posterior duct. Two efferent salivary ducts, which connect with the posterior lobe, fuse to form a common duct. The accessory gland is composed of three parts: a greatly tortuous and folded accessory salivary tube, a circlet of gular gland constituting of several acini of the same size, and a non-collapsible accessory salivary duct. The digitate lobules and gular glands possess secretory cells containing abundant secretory granules vary in size, shape, and electron density, as might indicate different materials are synthesized in different secretory regions. The anterior-posterior duct lines with a player of cuticular lining, and cells beneath the cuticular lining lack of basal infoldings, as suggests the duct serves just to transport secretions. The accessory salivary duct is lined with cuticular lining; cells of the duct have well developed basal infoldings associated with abundant mitochondria, as probably suggests the duct is a reabsorptive region of ions. The cells of the accessory salivary tube possess deep basal infoldings and well developed apical dense microvilli, indicating the cells of the tube are secretory in function. Concentric lamellar structures and a peculiar structure with abundant membrane-bound vesicles and secretory granules are observed for the first time, but their derivation and function remain unclear. The morphology and ultrastructure differences observed in the principal glands and accessory gland of the salivary glands of K. caelatata indicate that the sheath saliva was secreted by the principal glands, and the watery saliva was secreted by the accessory salivary glands. Rod-shaped microorganisms are found in the salivary glands (i.e., accessory salivary duct, gular gland, and long digitate lobule of salivary glands) for the first time, and their identity, function, and relationship to microorganisms residing in the salivary glands and/or other parts of alimentary canal of other cicadas need to be investigated further.

Clinical analysis of 42 cases of chronic expanding intracerebral hematoma

To summarize our own experiences of managing chronic expanding intracerebral hematoma (CEICH) and discuss its diagnosis and treatment. The courses of CEICH, clinical and imaging features, intraoperative findings, pathological examinations and follow-up outcomes were reviewed retrospectively. The relevant literatures were reviewed simultaneously. The course of CEICHs ranged from 22 days to 10 years. Twenty-three cases (54.8%) were misdiagnosed as cystic gliomas, cystic gliomas, brain cysticercoses, brain abscesses and tumor strokes, etc. The misdiagnostic rate had decreased to 19.0% since June 1997. Thirty-eight patients underwent surgical operations and 4 had puncture drainage of hematoma. There was no operative death. Thirty-three cases achieved an excellent recovery and 9 cases had varying degrees of nervous dysfunctions. The follow-up period was 1-21 years. One patient had recurrence after 10 years. Among the cases of multiple CEICH, two lesions underwent no surgical treatment. One increased obviously after 7 years and another disappeared. The following five points may be used as the diagnostic criteria of CEICH: (1) intracerebral cystic space-occupying lesions on brain images; (2) circular or circle-like enhancement around lesions; (3) a mixed signal of concentric circular lamellar structures on MRI T1WI; (4) abnormal vascular lesions on CTA, MRA or DSA; (5) clinical signs and symptoms of slow progress of intracranial pressure. CEICHs with clinical symptoms of local mass effect shall be obliterated surgically. The abnormal tissues in cyst wall of hematoma should be resected. Small hematomas (< 2 cm) may be followed up.

Retroperitoneal liposarcoma with lamellar bone inside

In December, 2006, a 65-year-old Japanese man with chronic renal failure was referred to our hospital for the assessment of a large retroperitoneal mass (fi gure A). The mass was resected surgically, and the histopathological diagnosis was an undiff erentiated liposarcoma with areas of osseous metaplasia. 3 years later, a recurrent liposarcoma with bony structures inside (fi gure B) was found in the retoperitoneal space. The resected specimen was viewed by bone histomorphometry after tetracycline double labelling. The bone islands surrounded by adipose tissue showed concentric lamellar structures, with a few osteocytes between the lamella, surrounded by tetracycline double labelling, an osteoid layer, osteoblasts, and fi brous tissue (fi gure C). These fi ndings suggested that osteoid deposit and mineralisation were taking place outwardly. More immature woven bone and cartilaginous tissue were also seen inside the mass. These fi ndings are compatible with the cancer stem cell theory and suggest that our patient’s tumour derived from a mesenchymal stem-like cell that had the potential to diff erentiate into cartilage, bone and adipocytes.