Seasonal variation in glycoconjugates of the pedal glandular system of the rayed Mediterranean limpet,Patella caerulea (Gastropoda: Patellidae)

Glycoconjugates secreted by the pedal system of the rayed limpet, Patella caerulea, were characterised in situ by histochemical and lectin-histochemical methods in individuals collected around the annual cycle, in November, March, and June. Stainings with periodic acid–Schiff (PAS), Alcian blue pH 2.5 (AB pH 2.5), Alcian blue pH 1.0 (AB pH 1.0), high-iron diamine–Alcian blue pH 2.5 and lectin binding assays with 9 lectins (Con A, WGA, succinylated-WGA, PNA, DBA, SBA, AAA, UEA-I, LTA) were performed. Four secreting cell types were observed in the sole, one in the peripheric region, and two in the sidewall. Glycoconjugate composition varied among cell types and also in one and the same cell type throughout the year. β-Elimination followed by PAS and AB pH 2.5 stainings indicated that most saccharidic chains were O-linked to the protein backbone. Secretion by sole and peripheric region was acidic, carboxylated and/or sulfated, whereas that of the sidewall was neutral. Glucosaminylated and 1,4-fucosylated residuals were predominant in the cell types along the year, 1,2-fucosylated residuals being observed only in the sidewall cells in June. Mannosylated and/or glycosylated residuals were observed in all cells mostly in November. Galactosylated/galactosaminylated residuals were present mostly in the sidewall cells and in the sole subepidermal mucocytes in June. Mannosylated and/or glycosylated residuals in November are probably linked to gonad maturation or to higher locomotion and foraging activity, whereas galactosaminylation in the sole cells and 1,2-fucosylation and glucosaminylation in the sidewall cells in June are linked to a prolonged stationary state, increasing water adsorption to counteract dehydration and/or to modulate microbial interactions.     

Effects of global climate change on marine and estuarine fishes and fisheries

Global climate change is impacting and will continue to impact marine and estuarine fish and fisheries. Data trends show global climate change effects ranging from increased oxygen consumption rates in fishes, to changes in foraging and migrational patterns in polar seas, to fish community changes in bleached tropical coral reefs. Projections of future conditions portend further impacts on the distribution and abundance of fishes associated with relatively small temperature changes. Changing fish distributions and abundances will undoubtedly affect communities of humans who harvest these stocks. Coastal-based harvesters (subsistence, commercial, recreational) may be impacted (negatively or positively) by changes in fish stocks due to climate change. Furthermore, marine protected area boundaries, low-lying island countries dependent on coastal economies, and disease incidence (in aquatic organisms and humans) are also affected by a relatively small increase in temperature and sea level. Our interpretations of evidence include many uncertainties about the future of affected fish species and their harvesters. Therefore, there is a need to research the physiology and ecology of marine and estuarine fishes, particularly in the tropics where comparatively little research has been conducted. As a broader and deeper information base accumulates, researchers will be able to make more accurate predictions and forge relevant solutions.     

Effects of altered estuarine submerged macrophyte bed cover on the omnivorous Cape stumpnose Rhabdosargus holubi

The ecological importance of submerged macrophyte beds to fishes within estuaries was investigated through the example of the ubiquitous Cape stumpnose Rhabdosargus holubi, an omnivorous, vegetation and estuary-dependent species, using stable-isotope techniques and long-term abundance (catch-per-unit-effort) data from the East Kleinemonde Estuary, South Africa. Outputs from a Bayesian mixing model using δ(13) C and δ(15) N signatures indicated that the submerged macrophytes Ruppia cirrhosa and Potamogeton pectinatus were not a primary source of nutrition for R. holubi, confirming previous work that revealed that macrophytes are consumed but not digested. Long-term seine netting data showed reduced abundance of R. holubi during a prolonged period of macrophyte senescence, suggesting that submerged macrophyte habitats provide shelter that reduces mortality (predation risk) and a food-rich foraging area.     

Ultrastructure of the labellar epidermis in selected Maxillaria species (Orchidaceae)

The ultrastructure of the labellar epidermis of 13 species of Maxillaria and one hybrid was examined using low-vacuum scanning electron microscopy (SEM). The labellum may be homogeneous and glabrous or papillose, comprising one type of cell only, or heterogeneous with papillae, uniseriate trichomes and/or glands in various combinations. The trichomes are unbranched and multicellular with pointed or truncated tips. Moreover, in some taxa, moniliform trichomes occur, and these are thought to fragment with the formation of pseudopollen. Homogeneous and heterogeneous labellar organization may represent separate evolutionary lines. Preliminary results suggest that labellar features may provide additional taxonomic characters allowing determination of intrageneric affinities.     

New caerin antibacterial peptides from the skin glands of the Australian tree frog Litoria xanthomera

The secretion of the skin glands of the ‘orange-thighed frog’ Litoria xanthomera contains seven peptides. One of these is the known hypotensive peptide caerulein. Two new peptides, caerin 1.6 [GLFSVLGAVAKHVLPHVVPVIAEKL(NH₂)], and caerin 1.7 [GLFKVLGSVAKHLLPHVAPVIAEKL(NH₂)] show antibacterial properties. Two other peptides lack the first two amino acid residues of caerins 1.6 and 1.7 and show no antibacterial activity. The identification of the peptides in Litoria xanthomera confirms that this species is related to Litoria caerula, Litoria gilleni and Litoria splendida but not as closely as those three species are related to each other. © 1997 European Peptide Society and John Wiley & Sons, Ltd.     

Freshwater and estuarine fishes of the Russian Arctic coast (the Swedish–Russian Expedition 'Tundra Ecology—94')

The distribution of estuarine and freshwater fish species caught during the Swedish-Russian Expedition' Tundra Ecology–94'is presented. Thirteen sites along the Russian part of the Arctic Sea coast were sampled and a total of 21 fish species of the families Salmonidae, Coregonidae, Thymallidae, Osmeridae, Cyprinidae, Catostomidae, Balitoridae, Gadidae, Gasterosteidae, Percidae, Cottidae, Pleuronectidae were recorded. Some records were new to particular basins.     

Evaluation of the effects of cosmetic or dermo-pharmaceutical products on cutaneous energy metabolism using the Episkin model of reconstructed epidermis

This study was implemented to test the Episkin model of reconstructed epidermis in the evaluation of the efficacy of cosmetic or dermopharmaceutical products on cutaneous energy metabolism. The energy metabolism is evaluated by measuring the concentration of intracellular ATP by a method using an ultrasensitive bioluminescent reaction. The work presented compares results obtained in reconstructed epithelium and monolayer primary cultures of human keratinocytes.After application of a hydrosoluble product, the increase in intracellular ATP is identical in a monolayer culture of keratinocytes (+239±18% versus control) and in Episkin (+248±21% versus control). An emulsion was also tested on the two models. It is only possible to test the emulsion at a dilution of under 0.05% on a keratinocyte culture, and this means that the real efficacy of the product is underestimated (+145±18% versus control). The three-dimensional model enables the application of the undiluted emulsion, and the results show an increase in intracellular ATP of +420±80% versus control: products in final formulation can be tested in normal conditions of use.Abbreviations BPE bovine pituitary extract - DMEM Dulbecco's modified Eagle's medium - EDTA ethylene diamine tetraacetic acid - EGF epidermal growth factor - K-SFM keratinocytes serum free medium - MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide - O/W oil in water - PBS phosphate-buffered saline     

Sediment dynamics and estuarine circulation in the turbidity maximum of the Elbe river

Data are presented from several campaigns concerning to the residual transport of water, salt and suspended particulate matter (SPM) at different depths and at different longitudinal and cross-sectional locations in the Elbe Estuary, Northern Germany. The intratidal behaviour of SPM is analysed and explained in terms of cyclic settling and resuspension. Superimposed on these local processes are advective horizontal transports of water and SPM in different vertical layers. Tidally averaged horizontal fluxes of salinity and SPM have been calculated at different depths. For the most part, they show upstream directed transport in the bottom layers, while in the upper water column SPM is carried towards the sea. Examples of the influence of vertical salinity gradients on SPM dynamics, of the lateral variation of residual transport of water and SPM, and the effects of a runoff peak are also presented.     

A new species of the genus Helcogramma (Blenniiformes, Tripterygiidae) from Taiwan

A new species of triplefin fish (Blenniiformes: Tripterygiidae), Helcogramma williamsi, is described from six specimens collected from southern Taiwan. This species is well distinguished from its congeners by possessing 13 second dorsal-fin spines; third dorsal-fin rays modally 11; anal-fin rays modally 19; pored scales in lateral line 22-24; dentary pore pattern modally 5+1+5; lobate supraorbital cirrus; broad, serrated or palmate nasal cirrus; first dorsal fin lower in height than second; males with yellow mark extending from anterior tip of upper lip to anterior margin of eye and a whitish blue line extending from corner of mouth onto preopercle. Comparisons and a diagnostic key are provided for the species of Helcogramma now known from Taiwan: Helcogramma fuscipectoris, Helcogramma inclinata, Helcogramma striata, Helcogramma trigloides, and the newly recorded, Helcogramma rhinoceros.     

Musculoskeletal morphology and regionalization within the dorsal and anal fins of bluegill sunfish (Lepomis macrochirus)

Ray‐finned fishes actively control the shape and orientation of their fins to either generate or resist hydrodynamic forces. Because of the emergent mechanical properties of their segmented, bilaminar fin rays (lepidotrichia), and actuation by multiple muscles, fish can control the rigidity and curvature of individual rays independently, thereby varying the resultant forces across the fin surfaces. Expecting that differences in fin‐ray morphology should reflect variation in their mechanical properties, we measured several musculoskeletal features of individual spines and rays of the dorsal and anal fins of bluegill sunfish, Lepomis macrochirus, and assessed their mobility and flexibility. We separated the fin‐rays into four groups based on the fin (dorsal or anal) or fin‐ray type (spine or ray) and measured the length of the spines/rays and the mass of the three median fin‐ray muscles: the inclinators, erectors and depressors. Within the two ray groups, we measured the portion of the rays that were segmented vs. unsegmented and branched vs. unbranched. For the majority of variables tested, we found that variations between fin‐rays within each group were significantly related to position within the fin and these patterns were conserved between the dorsal and anal rays. Based on positional variations in fin‐ray and muscle parameters, we suggest that anterior and posterior regions of each fin perform different functions when interacting with the surrounding fluid. Specifically, we suggest that the stiffer anterior rays of the soft dorsal and anal fins maintain stability and keep the flow across the fins steady. The posterior rays, which are more flexible with a greater range of motion, fine‐tune their stiffness and orientation, directing the resultant flow to generate lateral and some thrust forces, thus acting as an accessory caudal fin. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc.     

A study to determine the underlying reason for abnormal glandular cytology and the formulation of a management protocol

A retrospective review is presented of 89 patients with glandular dyskaryosis in order to formulate a management protocol. Fifteen patients had cervical intraepithelial neoplasia (CIN) without glandular abnormality (17%). One patient had adenocarcinoma in situ of the cervix and one patient had vaginal intraepithelial neoplasia (VAIN) grade III. Twenty‐two patients had endometrial carcinoma (24.5%) and 11 patients had cervical carcinoma (12.5%). Of the patients presenting with post‐menopausal bleeding as well as having glandular dyskaryosis, 69% had a gynaecological malignancy. In conclusion, colposcopy and out‐patient endometrial sampling are recommended in all cases. Patients with abnormal endometrial sampling require hysteroscopy. Cone biopsy is necessary to exclude occult glandular disease if cytology remains abnormal despite negative colposcopy and sampling.     

Touch sensation by pectoral fins of the catfish Pimelodus pictus

Mechanosensation is fundamental to many tetrapod limb functions, yet it remains largely uninvestigated in the paired fins of fishes, limb homologues. Here we examine whether membranous fins may function as passive structures for touch sensation. We investigate the pectoral fins of the pictus catfish (Pimelodus pictus), a species that lives in close association with the benthic substrate and whose fins are positioned near its ventral margin. Kinematic analysis shows that the pectoral fins are held partially protracted during routine forward swimming and do not appear to generate propulsive force. Immunohistochemistry reveals that the fins are highly innervated, and we observe putative mechanoreceptors at nerve fibre endings. To test for the ability to sense mechanical perturbations, activity of fin ray nerve fibres was recorded in response to touch and bend stimulation. Both pressure and light surface brushing generated afferent nerve activity. Fin ray nerves also respond to bending of the rays. These data demonstrate for the first time that membranous fins can function as passive mechanosensors. We suggest that touch-sensitive fins may be widespread in fishes that maintain a close association with the bottom substrate.     

Cellular and molecular processes of regeneration, with special emphasis on fish fins

The phenomenon of 'epimorphic regeneration', a complete reformation of lost tissues and organs from adult differentiated cells, has been fascinating many biologists for many years. While most vertebrate species including humans do not have a remarkable ability for regeneration, the lower vertebrates such as urodeles and fish have exceptionally high regeneration abilities. In particular, the teleost fish has a high ability to regenerate a variety of tissues and organs including scales, muscles, spinal cord and heart among vertebrate species. Hence, an understanding of the regeneration mechanism in teleosts will provide an essential knowledge base for rational approaches to tissue and organ regeneration in mammals. In the last decade, small teleost fish such as the zebrafish and medaka have emerged as powerful animal models in which a variety of developmental, genetic and molecular approaches are applicable. In addition, rapid progress in the development of genome resources such as expressed sequence tags and genome sequences has accelerated the speed of the molecular analysis of regeneration. This review summarizes the current status of our understanding of the cellular and molecular basis of regeneration, particularly that regarding fish fins.     

菱的腺毛发育及分泌活动的超微结构研究

菱的腺毛由单列圆筒状细胞组成,具有短暂的分泌功能。它们起源于叶片远轴面、叶柄的表皮细胞以及苗端茎轴、花柄的表皮细胞。处于分泌期的腺毛细胞其胞质浓厚,液泡化程度小,细胞具丰富的线粒体、高尔基体。腺毛丧失了分泌功能后即发育成为表皮毛。粘液物质由高尔基体分泌小泡携带至腺毛细胞侧壁,经胞吐与渗透结合的方式分泌至细胞外,粘液的化学成分主要为多糖。     

Ultrastructure of posterior sternal glands of Macrotermes annandalei (Silvestri): new members of the sexual glandular set found in termites (Insecta)

In female alates of Macrotermes annandalei, two types of abdominal glands are involved in the secretion of sex pheromone. Tergal glands are found at the anterior margin of tergites 6-10 and posterior sternal glands (PSGs) are located at the anterior margin of sternites 6-7. The cytological features of both types of glands are quite similar. The fine structural organization of PSGs is studied more precisely and described for the first time. The glandular cuticle is pitted with narrow apertures corresponding to the openings of numerous subcuticular pouches. Several Class 3 glandular units open in each pouch. One canal cell and one secretory cell make an individual glandular unit. The canal cell is enlarged apically and is connected with the other canal cells to form a common pouch. Based on the structural features found in these glands, we propose a common secretory process for PSGs and tergal glands. During the physiological maturation of alates inside the nest, secretory vesicles amass in the cytoplasm of secretory cells, while large intercellular spaces collapse the cuticular pouches. At the time of dispersal flight, pouches are filled with the content of secretory vesicles while intercellular spaces are sharply reduced. After calling behavior, no secretion remains in the glands and pouches collapse again, while secretory cells are drastically reduced in size. The structure and the secretory processes of PSGs and tergal glands are compared to those of abdominal sexual glands known in termites.     

P-cadherin expression in glandular lesions of the uterine cervix detected by liquid-based cytology

OBJECTIVE: To study P-cadherin aberrant expression as a possible marker for cervical adenocarcinomas in cytological samples. METHODS: We studied P-cadherin immunoexpression in liquid-based cervical cytology samples of biopsy-proven cervical lesions. RESULTS: We found a statistically significant correlation between P-cadherin expression and a cytological diagnosis of malignancy, either glandular or squamous (P < 0.0001). Twenty-two of 33 malignant cases showed P-cadherin membrane staining. None of the 30 benign cases tested showed membrane staining, but three of them displayed an aberrant nuclear P-cadherin expression. CONCLUSIONS: We concluded that P-cadherin can be used to discriminate between malignant and benign cervical cytological specimens, but not to discriminate glandular from squamous lesions.     

Ultrastructure of larval epidermis of the nemertean <Emphasis Type="Italic">Quasitetrastemma stimpsoni</Emphasis> (Chernyshev, 1992) (Hoplonemertea)

The ultrastructure of the epidermis of free-swimming larvae of the nemertean Quasitetrastemma stimpsoni was examined. At about 24 hours after hatching, the provisional epithelium of larva is 28–35 μm thick and consists of two layers of cells—peripheral and basal. The peripheral layer consists of multiciliated cells and two kinds of gland cells. The “basal cup” zone is formed from the vacuoles of basal cells. At about 50 hours after hatching, the definitive epithelium is 14–17 μm thick and exhibits a typical hoplonemertean structure. However, it has numerous yolk vesicles, few processes of granular basal cells, and a weakly developed dermis. Thus, the replacement of the provisional epithelium by the definitive one occurs in Q. stimpsoni at an earlier stage, compared to the hidden larva of Tetrastemma candidum.     

Dynamics of estrogen induction of glandular kallikrein in the rat anterior pituitary

Glandular kallikrein has recently been identified as an estrogen-induced protein of the rat anterior pituitary. This study examined the dynamics of the estrogen induction of anterior pituitary glandular kallikrein in the ovariectomized rat. The estrogen induction of uterine dry weight was also examined for purposed of comparison. 17β-Estradiol (0.1–100 μg/day) produced dose-dependent increases in anterior pituitary glandular kallikrein, with the highest dose producing a 60-fold increase. Time-course studies demonstrated that a lag phase of 2–3 days was required before these estrogen effects on glandular kallikrein became evident, and levels were still rising between 7 and 10 days of treatment. The dynamics of the estrogen induction of glandular kallikrein resembled the estrogen induction of uterine dry weight with regard to estrogen sensitivity and the presence of a lag phase before estrogen-induced increases. However, uterine dry weight responde more rapidly to estrogen than did anterior pituitary glandular kallikrein, and reached a plateau after 5 days of estrogen treatment.     

Effects of salinity on growth and on valve morphology of five estuarine diatoms

The effects of salinity on the growth and valve morphology of five benthic estuarine diatoms (Nitzschia pusilla, N. frustulum, N. palea, N. filiformis var. conferta and Eolimna subminuscula), isolated from both freshwater and brackish/marine habitats, were investigated. The four Nitzschia strains grew well over a broad salinity range, though some (N. pusilla, N. frustulum) showed a broader salinity range tolerance (from fully saline down to at least 9.5 ppt) than others (N. palea, N. filiformis var. conferta had reduced growth at salinities of 16 ppt and above). Salinity significantly affected the valve morphology of the five strains studied. However, there was no consistent pattern in either the morphological characters affected or the direction of the effects. Although significant, the effects of salinity on valve morphology were very small and therefore it seems that the taxonomic usefulness of some of the classical taxonomical characters is not undermined.