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Body Cavity (body + cavity)
Selected AbstractsWhen an epithelium ceases to exist , an ultrastructural study on the fate of the embryonic coelom in Epiperipatus biolleyi (Onychophora, Peripatidae)ACTA ZOOLOGICA, Issue 3 2004Georg Mayer Abstract It is an accepted fact that fusion between the coelomic cavities and the primary body cavity occurs during development in the Arthropoda. However, such a fusion is much disputed in the Onychophora. In order to clarify this subject, the fate of embryonic coelomic cavities has been studied in an onychophoran. Ultrastructural investigations in this paper provide evidence that embryonic coelomic cavities fuse with spaces of the primary body cavity in Epiperipatus biolleyi. During embryogenesis, the somatic and splanchnic portions of the mesoderm separate and the former coelomic linings are transformed into mesenchymatic tissue. The resulting body cavity therefore represents a mixture of primary and secondary (coelomic) body cavities, i.e. the ,mixocoel'. The nephridial anlage is already present, when the ,mixocoel' is formed, although there is no trace of a sacculus yet. The lumen of the nephridial anlage, thus, communicates with the newly formed ,mixocoel'. Accordingly, the lumen of the nephridial sacculus cannot be regarded as a kind of ,persisting coelomic cavity' in E. biolleyi. Our findings support the hypothesis that the ,mixocoel' was already present in the common stem species of the Onychophora and Euarthropoda. [source] Ultrastructure of the body cavities in Phylactolaemata (Bryozoa)JOURNAL OF MORPHOLOGY, Issue 3 2009Alexander Gruhl Abstract Only species belonging to the bryozoan subtaxon Phylactolaemata possess an epistome. To test whether there is a specific coelomic cavity inside the epistome, Fredericella sultana, Plumatella emarginata, and Lophopus crystallinus were studied on the ultrastructural level. In F. sultana and P. emarginata, the epistome contains a coelomic cavity. The cavity is confluent with the trunk coelom and lined by peritoneal and myoepithelial cells. The lophophore coelom extends into the tentacles and is connected to the trunk coelom by two weakly ciliated coelomic ducts on either side of the rectum. The lophophore coelom passes the epistome coelom on its anterior side. This region has traditionally been called the forked canal and hypothesized to represent the site of excretion. L. crystallinus lacks an epistome. It has a simple ciliated field where an epistome is situated in the other species. Underneath this field, the forked canal is situated. Compared with the other species, it is pronounced and exhibits a dense ciliation. Despite the occurrence of podocytes, which are prerequisites for a selected fluid transfer, there is no indication for an excretory function of the forked canal, especially as no excretory porus was found. J. Morphol. 2009. © 2008 Wiley-Liss, Inc. [source] Intracavitary cisplatin therapy for pediatric malignancies,PEDIATRIC BLOOD & CANCER, Issue 3 2010Howard M. Katzenstein MD Abstract Background Local control is essential for the successful treatment of pediatric solid tumors. Complete excision is often not possible and local control therapies are limited. Intracavitary cisplatin (IC-CDDP) may be utilized to supplement local control. The aim of the study was to determine the toxicity and efficacy of locally instilled intracavitary cisplatin in patients with recurrent tumors in closed body cavities. Procedure From 2001 to 2009, 12 patients (1,20 years) with recurrent or unresectable malignant tumors were treated with IC-CDDP. Nine had pulmonary lesions. Three patients had abdominal tumors. CDDP (200,mg/m2) was instilled by chest tube or Tenckhoff catheter. Patients were shifted every 15,30,min to allow distribution. After 4,hr, residual was drained by gravity. In 10/13 courses, sodium thiosulfate (STS) was administered to prevent nephrotoxicity. Three other patients received amifostine. Results Malignant pleural effusions resolved in 5/7 patients. This response was temporary in three patients. No patients had ascites prior to treatment. Three patients are alive and disease-free, 18 months, 4 years, and 6 years from treatment. They also had surgery and chemotherapy. Transient renal toxicity was noted in most patients. One patient, treated with amifostine, had persistent renal dysfunction. Conclusions IC-CDDP was effective in treating malignant pleural effusions and may be a palliative option for refractory disease. Long-term survival was achieved in two patients, treated at first diagnosis. The benefit of IC-CDDP in these patients is difficult to assess. Renal dysfunction is usually mild, and typically resolves, but warrants preventive measures with IC-CDDP therapy. Pediatr Blood Cancer. 2010;55:452,456. © 2010 Wiley-Liss, Inc. [source] Human herpes virus 8-unrelated primary effusion lymphoma-like lymphoma: report of a rare case and review of the literatureAPMIS, Issue 3 2009CAFER ADIGUZEL Primary effusion lymphoma (PEL) is a very rare type of lymphoma usually confined to the body cavities predominantly in immunosupressed patients infected with human herpes virus 8 (HHV-8). The new term for HHV-8 independent PEL is HHV8-unrelated PEL-like lymphoma. We describe an 89-year-old human immunodeficiency virus (HIV)-negative male patient with HHV8-unrelated PEL-like lymphoma in the pleura. No hepatosplenomegaly or lymphadenopathy was detected. Chest radiography and computed tomography revealed right pleural effusion, but no evidence of tumor mass or lymph node enlargement. Cytological analysis of the pleural effusion revealed a high-grade lymphoma with round nuclei, prominent nucleoli and abundant cytoplasm with immunophenotypes positive for CD45, CD30, CD38, CD7 and CD71. Because of the advanced age, no chemotherapy was given. Effusion resolved spontaneously. One year after the diagnosis, a new pleural effusion developed at the left side. Following thoracentesis and pleurodesis, the patient remained in complete remission for 40 months. To date, 30 cases of HHV8-unrelated PEL-like lymphoma/HIV negative have been reported in the literature. The outcome of the HHV8-unrelated PEL-like lymphoma patients who were HIV negative seems to be better than HIV- and HHV-8-positive PEL. [source] Vascular endothelial growth factor in edematous mouse embryos induced by retinoic acid in uteroCONGENITAL ANOMALIES, Issue 2 2001Yoshiko Yasuda ABSTRACT, Vascular endothelial growth factor (VEGF) is induced by hypoxic environment and contributes to vascular formation in both developing embryos and adults. Exogenous retinoic acid (RA) induces avascular yolk sacs with anemic stunted embryos of day 9 and 10 of gestation when RA is given to pregnant mice on day 6, 6.5 or 7 of pregnancy (Yasuda et al., 1996). We undertook the present studies to find out whether VEGF is activated and plays any role in those RA-exposed embryos. Embryos were obtained from dams given 60 mg/kg of RA on day 6 or 7 of pregnancy and sacrificed three days later. Most RA-exposed embryos showed edematous swelling without prominent vascular nets, but had beating heart tubes on day 9 and day 10 of gestation. Microscopic examination of developing tissue components showed various degrees of degeneration, and distension of the dorsal aorta when the body cavity was dosed. Northern blot analysis revealed expression of VEGF mRNA in the RA-exposed and control embryos. The highest expression of VEGF mRNA was seen in the embryos of day 10 exposed to RA on day 7, and these embryos had a significantly lower ATP content than did the controls (p < 0.01). Immunoreactive VEGF was detectable in both experimental and control embryos; in the former it was especially visible in the distended neuroepithelium, endothelium and membranes. These VEGF-immunoreactive regions also expressed another permeability factor, bradykinin. These findings suggest that VEGF upregulated by hypoxic conditions in edematous embryos induced by RA exposure in utero acts as hyperpermeability. [source] Focal electroporation in ovoDEVELOPMENTAL DYNAMICS, Issue 12 2009J. E. Simkin Abstract Gene expression fields in embryogenesis are spatially precise and often small, so experimental gene expression often requires similar spatial definition. For in ovo electroporation, typically a gene construct is injected into a natural body cavity in the embryo prior to electroporation. Limited control of the size and location of the electroporated field can be obtained by varying electrode placement and geometry, and by altering the miscibility and viscosity of the construct vehicle but it is difficult to tightly constrain electroporation to small regions. Electroporation of different constructs in close proximity has not been possible. We show that loading the construct into an agarose bead, which is then microsurgically implanted, allows for focal electroporation. Different constructs can be electroporated in close proximity by emplacing several agarose beads. This technique is simple, cheap, rapid, and requires no more specialised equipment than that required for conventional in ovo electroporation. Developmental Dynamics 238:3152,3155, 2009. © 2009 Wiley-Liss, Inc. [source] Detection of tumor cells in body cavity fluids by flow cytometric and immunocytochemical analysisDIAGNOSTIC CYTOPATHOLOGY, Issue 8 2006Awtar Krishan Ph.D. Abstract Measurement of electronic volume versus DNA content of nuclei can be used to discriminate between normal and malignant cells. Epithelial membrane antigen immunocytochemistry (EMA-ICC), a helpful ancillary test in body cavity fluids, is not universally accurate for detecting malignancy in effusions. The current study was undertaken to determine if multiparametric flow cytometry (based on simultaneous analysis of light scatter, nuclear volume, DNA, and nuclear protein content) in combination with (EMA-ICC) could be used for the detection of malignant cells in peritoneal and pleural fluids. We studied 130 body cavity fluids (68 peritoneal and 62 pleural fluids) by conventional cytology and multiparametric laser flow cytometry. EMA-ICC was performed using EMA antibodies and L-SAB detection system (DakoCytomation, Carpinteria, CA). EMA-ICC had significantly higher sensitivity than conventional cytology (79% versus 59%, P = 0.016) and ploidy (79% versus 38%, P = 0.001). Cytology had significantly higher specificity than ploidy (97% versus 82%, P = 0.012). The differences in specificity between EMA-ICC and ploidy (87% versus 82%, P= 0.607) or EMA-ICC and cytology (87% versus 97%, P = 0.109) were not statistically significant. However, assuming serial testing, sensitivity increased significantly for the combinations of cytology and EMA-ICC (79.4%, P = 0.016) and cytology and ploidy (73.5%, P = 0.004) as compared to cytology alone (58.8%). Also, the combination of cytology and ploidy had a higher sensitivity than ploidy alone (73% versus 38%, P < 0.0001). However, the sensitivity associated with the three tests used in serial (85.3%) was not significantly different from the sensitivities corresponding to the combination of cytology and EMA-ICC (79%) or cytology and ploidy (73%). Multiparametric flow cytometry utilizing high resolution DNA, nuclear volume, protein measurement, and ICC, in combination with cytomorphology, may be a valuable tool for rapid identification of malignant cells in body cavity fluids. Diagn. Cytopathol. 2006;34:528,541. © 2006 Wiley-Liss, Inc. [source] When an epithelium ceases to exist , an ultrastructural study on the fate of the embryonic coelom in Epiperipatus biolleyi (Onychophora, Peripatidae)ACTA ZOOLOGICA, Issue 3 2004Georg Mayer Abstract It is an accepted fact that fusion between the coelomic cavities and the primary body cavity occurs during development in the Arthropoda. However, such a fusion is much disputed in the Onychophora. In order to clarify this subject, the fate of embryonic coelomic cavities has been studied in an onychophoran. Ultrastructural investigations in this paper provide evidence that embryonic coelomic cavities fuse with spaces of the primary body cavity in Epiperipatus biolleyi. During embryogenesis, the somatic and splanchnic portions of the mesoderm separate and the former coelomic linings are transformed into mesenchymatic tissue. The resulting body cavity therefore represents a mixture of primary and secondary (coelomic) body cavities, i.e. the ,mixocoel'. The nephridial anlage is already present, when the ,mixocoel' is formed, although there is no trace of a sacculus yet. The lumen of the nephridial anlage, thus, communicates with the newly formed ,mixocoel'. Accordingly, the lumen of the nephridial sacculus cannot be regarded as a kind of ,persisting coelomic cavity' in E. biolleyi. Our findings support the hypothesis that the ,mixocoel' was already present in the common stem species of the Onychophora and Euarthropoda. [source] Targeted disruption of a pupal hemocyte protein of Sarcophaga by RNA interferenceFEBS JOURNAL, Issue 20 2001Takeshi Nishikawa Previously, we purified a transmembrane protein with a molecular mass of 120 kDa (p120) that is exclusively expressed in pupal hemocytes of Sarcophaga. In this study, we demonstrated that double-stranded RNA (dsRNA) injected into the larval body cavity effectively inhibited the expression of p120 in pupal hemocytes. Thus, RNA interference (RNAi) was found to be a useful technique for creating pupal hemocytes with a loss-of-function of a specific protein. The p120-less pupal hemocytes generated by RNAi were found to have lost the ability to take up acetylated low density lipoprotein, indicating that p120 is a scavenger receptor specifically expressed on the surface of pupal hemocytes. [source] Biscoclaurine alkaloid cepharanthine inhibits the growth of primary effusion lymphoma in vitro and in vivo and induces apoptosis via suppression of the NF-,B pathwayINTERNATIONAL JOURNAL OF CANCER, Issue 6 2009Naoko Takahashi-Makise Abstract Primary effusion lymphoma (PEL) is a unique and recently identified non-Hodgkin's lymphoma that was originally identified in patients with AIDS. PEL is caused by the Kaposi sarcoma-associated herpes virus (KSHV/HHV-8) and shows a peculiar presentation involving liquid growth in the serous body cavity and a poor prognosis. As the nuclear factor (NF)- ,B pathway is activated in PEL and plays a central role in oncogenesis, we examined the effect of a biscoclaurine alkaloid, cepharanthine (CEP) on PEL derived cell lines (BCBL-1, TY-1 and RM-P1), in vitro and in vivo. An methylthiotetrazole assay revealed that the cell proliferation of PEL cell lines was significantly suppressed by the addition of CEP (1,10 ,g/ml). CEP also inhibited NF- ,B activation and induced apoptotic cell death in PEL cell lines. We established a PEL animal model by intraperitoneal injection of BCBL-1, which led to the development of ascites and diffuse infiltration of organs, without obvious solid lymphoma formation, which resembles the diffuse nature of human PEL. Intraperitoneal administration of CEP inhibited ascites formation and diffuse infiltration of BCBL-1 without significant systemic toxicity in this model. These results indicate that NF- ,B could be an ideal molecular target for treating PEL and that CEP is quite useful as a unique therapeutic agent for PEL. © 2009 UICC [source] Origin and development of the pronephros in the chick embryoJOURNAL OF ANATOMY, Issue 6 2003Tamiko Hiruma Abstract The process by which the pronephros develops was morphologically examined in chick embryos from Hamburger,Hamilton stage (ST) 8+ to ST34. The intermediate mesoderm, from which the pronephros arises, was first seen as a faint ridge of undifferentiated mesoderm between the segmental plate and lateral plate at ST8+. It formed a cell cord at the level of the 6th to the presumptive 13th somites at ST9 to ST10. This cell cord then separated into dorsal and ventral parts, the former becoming the nephric duct and the latter the tubules by ST14. The primordia of the external glomeruli (PEGs) appeared at ST15 through some epithelial cells protruding in the nephrostome (the opening of the nephric tubule into the body cavity). PEGs formed gradually in the caudal direction until ST18, while the pronephric tubules and PEGs in cranial locations disappeared. At this stage, only a few PEGs remained at the level of the 13th and 14th somites and these developed from ST23 to ST29 to become ultrastructurally similar to the glomeruli of the functional kidney. From these observations in the avian pronephros, we infer that the pronephric duct and tubules both form from a cell cord in the intermediate mesoderm and at the same time, but later develop differently. [source] Feeding ecology of wild migratory tunas revealed by archival tag records of visceral warmingJOURNAL OF ANIMAL ECOLOGY, Issue 6 2008Sophie Bestley Summary 1Seasonal long-distance migrations are often expected to be related to resource distribution, and foraging theory predicts that animals should spend more time in areas with relatively richer resources. Yet for highly migratory marine species, data on feeding success are difficult to obtain. We analysed the temporal feeding patterns of wild juvenile southern bluefin tuna from visceral warming patterns recorded by archival tags implanted within the body cavity. 2Data collected during 1998,2000 totalled 6221 days, with individual time series (n = 19) varying from 141 to 496 days. These data span an annual migration circuit including a coastal summer residency within Australian waters and subsequent migration into the temperate south Indian Ocean. 3Individual fish recommenced feeding between 5 and 38 days after tagging, and feeding events (n = 5194) were subsequently identified on 76·3 ± 5·8% of days giving a mean estimated daily intake of 0·75 ± 0·05 kg. 4The number of feeding events varied significantly with time of day with the greatest number occurring around dawn (58·2 ± 8·0%). Night feeding, although rare (5·7 ± 1·3%), was linked to the full moon quarter. Southern bluefin tuna foraged in ambient water temperatures ranging from 4·9 °C to 22·9 °C and depths ranging from the surface to 672 m, with different targeting strategies evident between seasons. 5No clear relationship was found between feeding success and time spent within an area. This was primarily due to high individual variability, with both positive and negative relationships observed at all spatial scales examined (grid ranges of 2 × 2° to 10 × 10°). Assuming feeding success is proportional to forage density, our data do not support the hypothesis that these predators concentrate their activity in areas of higher resource availability. 6Multiple-day fasting periods were recorded by most individuals. The majority of these (87·8%) occurred during periods of apparent residency within warmer waters (sea surface temperature > 15 °C) at the northern edge of the observed migratory range. These previously undocumented nonfeeding periods may indicate alternative motivations for residency. 7Our results demonstrate the importance of obtaining information on feeding when interpreting habitat utilization from individual animal tracks. [source] Modified method for external attachment of transmitters to birds using two subcutaneous anchorsJOURNAL OF FIELD ORNITHOLOGY, Issue 3 2008Tyler L. Lewis ABSTRACT Of the transmitter attachment techniques for birds, the subcutaneous anchor provides a secure attachment that yields relatively few secondary effects. However, the use of subcutaneous anchors has been limited by transmitter size and retention time. Using a modified method of attachment that utilized two subcutaneous anchors, we deployed 69 GPS transmitters, plus 13 VHF transmitters that were similar in size and weight to GPS models, on Pacific Black Brant (Branta bernicla nigricans). Prior to our study, only harnesses were used for attaching GPS transmitters on birds, mainly because GPS transmitters are too large for other external attachment techniques and implantation in the body cavity attenuates the GPS signal. Thus, to increase the size capacity of anchor attachment and to avoid the well-documented negative effects of harnesses on behavior and survival, we added a second anchor at the transmitter's posterior end. The double-anchor attachment technique was quickly and easily accomplished in the field, requiring bird handling times of <10 min. Incidental recoveries of tagged Brant indicate a high degree of transmitter retention. Five recaptured birds (4,6 weeks after deployment) and eight killed by hunters (3,6 mo after deployment) retained their GPS transmitters. For studies involving the use of relatively large transmitters, the double-anchor method appears to provide a viable alternative for external attachment. SINOPSIS Entre las técnicas para montar radiotransmisores a aves, el anclaje subcutáneo provee una forma segura de montaje que presenta muy pocos efectos secundarios. Sin embargo, la utilidad del anclaje subcutáneo ha sido limitada por el tamaño del transmisor y el tiempo de retención en el ave. Utilizando un método modificado que utiliza dos puntos subcutáneos de anclaje, desarrollamos 69 transmisores GPS y 13 transmisores VHF que replicaban el tamaño y peso de modelos GPS, y que fueron montados en individuos del ganso, Branta bernicla nigricans. Previo a este estudio, solo se habían utilizado arneses para colocar radiotransmisores en los gansos. Esto fue así porque los tipo GPS son demasiado grandes para ser colocados de otra manera y cuando se implantan en la cavidad celómica, queda atenuada la señal del transmisor. Por tal razon, y para incrementar la capacidad de anclaje del transmisor y evitar el impacto negativo documentado en los arneses (en conducta y sobrevivencia), añadimos un segundo punto de anclaje en la parte posterior del transmisor. La técnica desarrollada fue fácil de aplicar en el campo y se hizo de forma rápida (<10 minutos). Recobros incidentales de gansos (4 recapturas, 4,6 semanas después) y ocho individuos cazados (3,6 meses después) indicaron un 100% de retención de los transmisores. Para estudios que conlleven transmisores de gran tamaño, el método de doble anclaje parece proveer una alternativa adecuada. [source] Effects of Ligula intestinalis on habitat use, predation risk and catchability in European minnowsJOURNAL OF FISH BIOLOGY, Issue 4 2001J. Museth The frequency of infection with Ligula intestinalis (Cestoda) in European minnow Phoxinus phoxinus, in a subalpine lake in Eastern Norway, did not differ between vegetated shoreline, exposed shoreline and non-vegetated localities >50 m from the shoreline. There was no difference in the vertical distribution of infected and uninfected individuals. The frequency of infection was higher among minnows in brown trout Salmo trutta stomachs than among those obtained by gillnets and minnow traps, suggesting that brown trout selectively preyed on infected minnows. Prevalence of infection decreased with increasing fish size, probably due to selective mortality among parasitized individuals. Within a given length-class, minnows captured by different sections of multi-mesh gillnets showed a significant increase in the frequency of infection with increasing mesh-size. Apparently, parasitized individuals had a higher catchability in gillnets due to increased girth caused by the plerocercoid in the body cavity. This may partly explain why the observed prevalence of infection was several times higher among minnows captured by gillnets than by minnow traps. [source] Comparative morphology of the hemolymph vascular system in scorpions,A survey using corrosion casting, MicroCT, and 3D-reconstructionJOURNAL OF MORPHOLOGY, Issue 5 2007Christian S. Wirkner Abstract Although scorpions are one of the better known groups of Arthropoda, detailed knowledge of their anatomy remains superficial. This contribution presents the first comprehensive investigation of the gross morphology of the scorpion vascular system, based on a survey of species representing all major lineages of the order, using classical and modern non-destructive techniques in combination with three-dimensional reconstruction. The investigation reveals that the hemolymph vascular system (HVS) of Scorpiones comprises a central pumping heart which extends the entire length of the mesosoma and is enclosed in a pericardium. Several arteries branch off the heart to supply different organs and body regions. Two different anterior aorta major branching patterns are identified among the species investigated. Arteries that branch off the anterior aorta system supply the appendages (chelicerae, pedipalps, and walking legs) and the central nerve mass with a complex arterial network. This study of the HVS of scorpions provides further evidence that the vascular systems of euarthropods can be highly complex. Use of the term "open circulatory system" within arthropods is re-emphasized, as it refers to the general organization of the body cavity (i.e. mixocoely) rather than to the complexity of the circulatory system. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Mosquito midguts and malaria: cell biology, compartmentalization and immunologyPARASITE IMMUNOLOGY, Issue 4 2006M. M. A. WHITTEN SUMMARY The malaria parasite Plasmodium has an absolute requirement for both a vertebrate and a mosquito host in order to complete its life cycle, and its interactions with the latter provide the focus for this review. The mosquito midgut represents one of the most challenging environments for the survival and development of Plasmodium, and is thus also one of the most attractive sites for novel targeted malaria control strategies. During their attempts to cross the midgut epithelium en route to the salivary glands, motile ookinetes are swiftly detected and labelled by mosquito recognition factors and targeted for destruction by a variety of immune responses that recruit killing factors both from the midgut and from other tissues in the surrounding body cavity. The exact interplay between these factors and the parasite is highly species- and strain-specific, as are the timing and the route of parasite invasion. These features are paramount to determining the success of the infection and the vector competence of the mosquito. Here we discuss recent advances in genomic analyses, coupled with detailed microscopical investigations, which are helping to unravel the identity and roles of the major players of these complex systems. [source] Bleeding of anaesthetized and exhausted Atlantic salmon: body cavity inspection and residual blood in pre-rigor and smoked fillets as determined by various analytical methodsAQUACULTURE RESEARCH, Issue 4 2010Ulf Erikson Abstract The bleeding efficiency of anaesthetized and exhausted Atlantic salmon was studied. Unbled fish were used as control groups for both treatments. Several analytical methods (computer vision, Minolta Chroma Meter, transflectance spectroscopy, haemoglobin iron and visual assessment of smoked fillets) were used to evaluate colour or residual blood contents of pre-rigor and smoked fillets. In all cases, the amount of residual blood in the fillets was modest and blood was not considered a quality problem in terms of fillet appearance. Perimortem stress did not affect residual blood contents of pre-rigor fillets. Only salting and smoking had a significant effect on filet colour. The low levels of residual blood was partly attributed to filleting shortly after killing allowing washing before the blood had time to coagulate. In addition, a computer vision method was developed for automated blood inspection of the body cavity after gutting and washing. A classifier (,no blood' or ,blood present') based on linear discriminant analysis was tested and the classification accuracy was over 90% as evaluated with the leave-one-out method. [source] Development of germ cells and reproductive biology in the sipunculid Phascolosoma esculentaAQUACULTURE RESEARCH, Issue 3 2009Xue-Ping Ying Abstract Sipuncula are of increasing interest for fisheries and aquaculture in China. Sustainable harvests will rely on a better knowledge of reproductive characteristics and stock enhancement. Here, we investigated the structural characteristics of and seasonal changes in germ cell development of the sipunculid Phascolosoma esculenta from the south-eastern coast of Zhejiang, China. An annual survey of egg numbers in the coelom (body cavity) fluid by light and electron microscopy of the females indicates that P. esculenta is dioecious. No defined gonad but dissociated germ cells were found in the coelomic cavity during the 1-year observation. The germ cells showed multiplication and development in the coelomic cavity. Reproduction took place from May to September, with a peak in July and August. The oogenesis can be divided into four phases: cell proliferation, pre-vitellogenesis, vitellogenesis and egg envelope formation and maturation. The process of spermatogenesis can also be divided into four phases: cell multiplication, cell growth, cell maturation and metamorphosis. Monthly changes in the relative number of eggs in each stage indicate that P. esculenta lays eggs in batches. The sperm thrives in the coelomic fluid in the form of cell groups with patterns of genesis and release similar to those of the eggs. Eggs of P. esculenta were fertilized only when reaching the nephridium. The sex ratio was about 1:1 throughout the year. [source] Molecular cloning and characterization of ATX1 cDNA from the mole cricket, Gryllotalpa orientalisARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 4 2006Iksoo Kim Abstract To search for an insect homologue of antioxidant protein 1 (ATX1), a mole cricket, Gryllotalpa orientalis, cDNA library was screened and a cDNA clone, which encodes a 73 amino acid polypeptide with a predicted molecular mass of 8.0 kDa and pI of 5.68, was isolated. The G. orientalis ATX1 (GoATX1) cDNA features both a MTCXXC copper-binding site in the N-terminus and a KTGK lysine-rich region in the C-terminus. The deduced amino acid sequence of the GoATX1 cDNA showed 63% identity to Drosophila melanogaster ATX1 and 55% to Ixodes pacificus ATX1. Northern blot analysis revealed the presence of GoATX1 transcripts in midgut, fat body, and epidermis. When H2O2 was injected into the body cavity of G. orientalis adult, GoATX1 mRNA expression was up-regulated in the fat body tissue. Fat body expression level of GoATX1 mRNA in the fat body was increased following exposure to low (4°C) and high (37°C) temperatures, suggesting that GoATX1 plays a protective role against oxidative stress caused by temperature shock. This is the first report about a functional role of insect ATX1 in antioxidant defense. Arch. Insect Biochem. Physiol. 61:231,238, 2006. © 2006 Wiley-Liss, Inc. [source] Variation in stickleback head morphology associated with parasite infectionBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009NIELS J. DINGEMANSE Parasites can affect host phenotypes, influencing their ecology and evolution. Host morphological changes occurring post-infection might result from pathological by-products of infection, or represent adaptations of hosts or parasites. We investigated the morphology of three-spined sticklebacks, Gasterosteus aculeatus, from a population naturally infected with Schistocephalus solidus, which grows to large sizes in their body cavity. We examined local effects of infection on trunk shape, which are imposed directly by the bulk of the growing parasite, and distant effects on head morphology. We show that trunk shape differed between infection classes, and was affected more severely in fish with heavier total parasite mass. We further show unexpected differences in head morphology. The heads of infected fish were reduced in size and differently shaped to those of non-infected fish, with infected fish having deeper heads. Importantly, both head size and shape were also affected more severely in fish with heavier total parasite mass. This latter result suggests that differences in morphology are caused by post-infection changes. Such changes may be incidental, evolutionarily neutral ,side effects' of infection. However, because head morphology affects foraging ecology, such changes are likely to have fitness consequences for hosts, and may constitute adaptations, either of hosts or of parasites. We discuss our finding in the context of the evolution of phenotypic plasticity, and suggest testable hypotheses examining the proximate mechanisms underlying these morphological effects and their potential evolutionary basis. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 759,768. [source] | |||||||||||||||||||