Electron microscopic studies on the palpi of Cybister fimbriolatus fimbriolatus (Say)

Summary The maxillary palpi of the predaceous diving beetle Cybister fimbriolatus fimbriolatus Say were observed by transmission and scanning electron microscopy. Scanning electron microscopy shows at least two types of sensilla at the tip of palp, which are referred to as circumvallate and naked sensilla. The former are innervated with outer segments of distal processes of sensory cells, but the latter are provided only with chitin and cuticular substances.This work was supported by Grant NB 04687 from the National Institutes of Health of the United States of America.We wish to express our gratitude to Prof. H. Stanley Bennett, Laboratories for Reproductive Biology, School of Medicine, University of North Carolina, Prof. G. Yasuzumi, Electron Microscope Research Laboratory, Department of Anatomy, Nara Medical University, and Prof. John E. Bardach, Department of Wildlife and Fisheries, School of Natural Resources, University of Michigan, for their valuable advice to the present work.     

根瘤蚜侵染不同抗性葡萄对根结形成及植株营养消耗的影响

为探讨不同抗性水平的葡萄砧木和品种被葡萄根瘤蚜Daktulosphaira vitifoliae Fitch侵染形成根结的状况及其对植株营养消耗的影响,采用盆栽方式接种根瘤蚜,测定了葡萄根结数量、质量及碳水化合物和脯氨酸含量等指标。结果表明：砧木5BB,1103P,SO4,3309C,101-14Mgt被根瘤蚜侵染后均不形成根结;140Ru,Lot和110R仅形成少量根结而不能形成根瘤;砧木贝达、栽培品种赤霞珠、巨峰和达米娜不仅能够形成根结和根瘤,而且根系腐烂程度严重。越敏感的品种形成的根结数量和体积越大,达米娜、巨峰和赤霞珠根结重占根重比例分别高达40.02％,37.08％和35.36％,百个根结质量分别是140Ru的4.4,3.5和433倍。3个形成根结的砧木的枝条生长量平均减少16.5％,而4个高感品种的生长量平均减少43％。根结质量与根结内的营养积聚呈正相关,其中根结质量与淀粉含量增加量的相关系数达0.94,与可溶性糖含量增加量的相关系数达0.81,与游离脯氨酸含量增加量的相关系数达0.93。     

Mesenchymal stem cells in maxillary sinus augmentation: A systematic review with meta-analysis

AIM: To investigate the effectiveness of mesenchymal stem cells (MSCs) in maxillary sinus augmentation (MSA), with various scaffold materials.METHODS: MEDLINE, EMBASE and SCOPUS were searched using keywords such as sinus graft, MSA, maxillary sinus lift, sinus floor elevation, MSC and cell-based, in different combinations. The searches included full text articles written in English, published over a 10-year period (2004-2014). Inclusion criteria were clinical/radiographic and histologic/ histomorphometric studies in humans and animals, on the use of MSCs in MSA. Meta-analysis was performed only for experimental studies (randomized controlled trials and controlled trials) involving MSA, with an outcome measurement of histologic evaluation with histomorphometric analysis reported. Mean and standard deviation values of newly formed bone from each study were used, and weighted mean values were assessed to account for the difference in the number of subjects among the different studies. To compare the results between the test and the control groups, the differences of regenerated bone in mean and 95% confidence intervals were calculated.RESULTS: Thirty-nine studies (18 animal studies and 21 human studies) published over a 10-year period (between 2004 and 2014) were considered to be eligible for inclusion in the present literature review. These studies demonstrated considerable variation with respect to study type, study design, follow-up, and results. Meta-analysis was performed on 9 studies (7 animal studies and 2 human studies). The weighted mean difference estimate from a random-effect model was 9.5% (95%CI: 3.6%-15.4%), suggesting a positive effect of stem cells on bone regeneration. Heterogeneity was measured by the I² index. The formal test confirmed the presence of substantial heterogeneity (I² = 83%, P < 0.0001). In attempt to explain the substantial heterogeneity observed, we considered a meta-regression model with publication year, support type (animal vs humans) and follow-up length (8 or 12 wk) as covariates. After adding publication year, support type and follow-up length to the meta-regression model, heterogeneity was no longer significant (I² = 33%, P = 0.25).CONCLUSION: Several studies have demonstrated the potential for cell-based approaches in MSA; further clinical trials are needed to confirm these results.     

Electrophysiological responses to sucrose from a gustatory sensillum on the larval maxillary palp of the spruce budworm,Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae)

The tip of the maxillary palp in the spruce budworm and other lepidoptera larvae contains a cluster of eight basiconic sensilla. Except for a few electrophysiological recordings from the entire group of these sensilla, no information is available on the response characteristics of any individual one. Using a compound microscope at 320x magnification, with a long working-distance objective, it has been possible to view individual sensilla and to record electrical responses from three of these to some gustatory stimuli in preliminary tests. One of them, sensillum (L1), contains a sugar-sensitive neuron whose responses to a range of sucrose concentrations are reported here. The physiological characteristics of this neuron differ from those of the known sugar-sensitive neuron in the lateral styloconic sensillum on the galea of these same insects. Input of chemosensory information about the same gustatory stimulus by more than one neuron in different mouthpart sensilla is discussed in relation to the feeding habits of the spruce budworm.     

Molecular interactions coordinating the development of the forebrain and face

From an architectural point of view, the forebrain acts as a framework upon which the middle and upper face develops and grows. In addition to serving a structural role, we present evidence that the forebrain is a source of signals that shape the facial skeleton. In this study, we inhibited Sonic hedgehog (Shh) signaling from the neuroectoderm then examined the molecular changes and the skeletal alterations resulting from the treatment. One of the first changes we noted was that the dorsoventral polarity of the forebrain was disturbed, which manifested as a loss of Shh in the ventral telencephalon, a reduction in expression of the ventral markers Nkx2.1 and Dlx2, and a concomitant expansion of the dorsal marker Pax6. In addition to changes in the forebrain neuroectoderm, we observed altered gene expression patterns in the facial ectoderm. For example, Shh was not induced in the frontonasal ectoderm, and Ptc and Gli1 were reduced in both the ectoderm and adjacent mesenchyme. As a consequence, a signaling center in the frontonasal prominence was disrupted and the prominence failed to undergo proximodistal and mediolateral expansion. After 15 days of development, the upper beaks of the treated embryos were truncated, and the skeletal elements were located in more medial and proximal locations in relation to the skeletal elements of the lower jaw elements. These data indicate that a role of Shh in the forebrain is to regulate Shh expression in the face, and that together, these Shh domains mediate patterning within the frontonasal prominence and proximodistal outgrowth of the middle and upper face.     

A new transplant bone for maxillary alveolar cleft

An innovative technique with distraction osteogenesis has been developed in our research group to explore autogenous bone transplantation into craniofacial bone defects. This technique was designed to investigate bone-marrow transplantion using a chondroid or fibula bone graft into simulated alveolar bone defects in mice in terms of the osteogenic process and activity. As an experimental model of maxillary alveolar bone cleft available for testing bone-inductive materials, a critical-size defect was formed in the pre-maxillary bone of male mice using a surgical trephine bur with a low-speed dental engine. Distraction osteogenesis was performed using an external fixation device. The osteotomy site was occupied by an external callus consisting of hyaline cartilage with a large quantity of chondroid bone. Moreover, bone remodelling with new bone formation was demonstrated 30 days after the transplantation. Bone adhesion was better in chondroid bone grafting than in fibula bone grafting. The present findings are the first to demonstrate the potential of chondroid bone transplantation as a new therapeutic system of bone grafting, suitable for bone substitutes in craniofacial bone defects.     

Craniomandibular morphology supporting the diphyletic origin of mangabeys and a new genus of the Cercocebus/Mandrillus clade, Procercocebus

Previous studies have noted skeletal and dental differences supporting the diphyletic origin of the mangabeys. Documented postcranial and dental characters are congruent with molecular data and thus support a close relationship between Cercocebus and Mandrillus (mandrills and drills) on the one hand and Lophocebus, Papio (baboons), and Theropithecus (geladas) on the other. Most of these characters, however, are postcranial and difficult to assess in the papionin fossil record because associated material is rare. In order to assess the African papionin fossil record and determine the evolutionary history of this group, cranial characters are critical. Here, a set of craniomandibular morphologies are documented that support the diphyletic origin of the mangabeys and more broadly support the molecular African papionin clades (i.e., Cercocebus/Mandrillus vs. Lophocebus/Papio/Theropithecus). These characters are then used to identify a series of fossil crania from Taung as representative of a new member of the Cercocebus/Mandrillus clade, Procercocebus antiquus. Procercocebus antiquus is closest in morphology to the extant taxon Cercocebus torquatus, and a probable ancestor-descendant relationship between Procercocebus and Cercocebus is suggested. Paleoecological reconstructions also suggest that a predator-prey relationship between African crowned eagles and the Procercocebus-Cercocebus lineage has existed for approximately the last two million years. Implications for Cercocebus biogeography and evolution are discussed.     

Flrt2 and Flrt3 have overlapping and non-overlapping expression during craniofacial development

Craniofacial morphogenesis is a complex multi-step process that involves numerous biological processes to coordinate the growth, proliferation, migration, and subsequent differentiation of the cranial neural crest cells. Members of the Fibronectin Leucine-Rich Transmembrane (Flrt) gene family have been previously reported to be widely expressed in the developing embryo. We mapped the expression of Flrt2 and Flrt3 at critical stages of craniofacial development and found that, during early craniofacial development, Flrt2 was highly expressed initially in the cranial neural crest cells and Flrt3 in the midbrain. Later both genes were expressed in the developing pharyngeal region. Flrt2 expression predominated in the neural crest-derived mesenchyme in the medial aspect of the developing frontonasal region in close relationships with the expression of Fgfr2, Shh, and Msx1, three genes shown previously to play critical roles in craniofacial development. Flrt2 was also present in the vomero-nasal organ, mandibular primodia, and the posterior aspects of the unfused and fused secondary palatal shelves. Flrt3, however, had a more restrictive expression, being present in the mesenchyme underlying the ectoderm of the medial nasal process and in the mandibular primordium and in regions undergoing outgrowth, in a pattern that overlapped with Bmp4 expression. Both Flrt2 and Flrt3 were later found to be present at sites of epithelial–mesenchymal interactions such as the developing tooth buds, hair follicles, and eye. Together the data suggested important roles for Flrt2 and Flrt3 in mediating events such as NCC migration, chondrogenesis and epithelial–mesenchymal interactions during craniofacial development.     

Ischial tuberosities and ischial callosities

Ischial callosities are specialised regions of skin and subdermal tissue in the form of fibro-fatty cushions with a tough, non-slip surface, firmly bound to the underlying ischial tuberosity. They occur in primates of the families Cercopithecidae and Hylobatidae. Ischial callosity usage helps animals to adopt stable sitting postures on the tops of branches, particularly during feeding, resting and sleeping. Callosity-like areas in pongids are mainly epidermal specialisations and differ in their development and usage from true callosities. They are similar to the para-callosity skin regions in some ground living cercopithecids. The ischial tuberosity in animals with true callosities has a flat surface which flares out from the lower end of the ischial body and which is devoid of muscle attachments. In animals without callosities the ischial tuberosity is not flared, has a curved surface, and acts as a site for muscle attachment. The ischial tuberosity is relatively broader in animals with callosities than in animals without callosities, although the absolute size of the specimens concerned must be taken into account. The combination of qualitative and quantitative features of fossil ischial tuberosities enables the presence or absence of callosities in these forms to be deduced. The recognition of these features in fossil material might be of use in the elucidation of the evolution of one type of primate arboreal adaptation.